Download icon

The evaluation of fiscal consolidation strategies

  1. Matus Senaj  Is a corresponding author
  2. Zuzana Siebertova  Is a corresponding author
  3. Norbert Svarda  Is a corresponding author
  4. Jana Valachyova  Is a corresponding author
  1. Council for Budget Responsibility, Slovakia
Research article
Volume 11(3) Winter 2018
Cite this article as: M. Senaj, Z. Siebertova, N. Svarda, J. Valachyova; 2018; The evaluation of fiscal consolidation strategies; International Journal of Microsimulation; 11(3); 39-58. doi: 10.34196/ijm.00188
13 tables

Tables

Table 1
Scaling of the simulation results.
Consolidation instrument Scaling coefficient Source of the official statistics for 2018
Personal income tax 1.17 Committee for the tax forecasts (Ministry of Finance)
Social and health insurance contributions 1.04 Committee for the tax forecasts (Ministry of Finance)
Social transfers 1.07 Information system on Government Budget
Value added tax 1.97 Committee for the tax forecasts (Ministry of Finance) When scaling the VAT, only the part paid by households is considered (estimated as the 87% of the total volume).

  1. Notes: Scaling coefficient is given as the ratio of the official statistics to simulated outcome from the model. Official statistics for every consolidation instrument is a forecasted value.

Table 2
Description of benchmark scenarios.
Scenario name Actual/baseline legislation Simulated policy change in scenario
Taxing labour income
PIT – 1 p.p. increase in the standard rate Two tax rates of personal income tax apply.
– 19% levied on yearly income up to 35 268 €
– 25% levied on income exceeding 35 268 €		 The standard rate is increased from 19% to 20%.
PIT – One tax rate Introduction of one tax rate of 22%. Basic and spouse tax allowances apply.
PIT – Decrease in tax allowances Basic and spouse tax allowance up to 3 830 € yearly (for each) can be deducted from individual taxable income. Basic and spouse tax allowance up to 3 630 € yearly (for each) can be deducted from individual taxable income.
Taxing consumption
VAT – 1 p.p. increase in the standard rate The standard rate is set to 20%, the reduced rate 10%. A number of goods are exempt from the tax base. The standard rate is increased to 21%.
VAT – abolition of the reduced rate The reduced rate is abolished, all goods are taxed at the standard rate 20%.
Payroll taxes: employees vs. employers
HIC – 1 p.p. increase in the rate paid by employers Health insurance contributions:
–4% employees
– 10% employers		 Increase of HIC paid by employers to 11%.
HIC – 1 p.p. increase in the rate paid by employees Increase of HIC paid by employees to 5%
Taxing firms
CIT – 1 p.p. increase in the rate Effective tax rate set to 19.5% Effective tax rate increased to 20.5%
Table 3
Description of benchmark scenarios.
Scenario name Actual/baseline legislation Simulated policy change in scenario
Cutting expenditures
Reduction of family related transfers and credits Family transfers include:
– parental allowance (monthly 214.70 €
– child benefits (monthly 23.69 € and 11.1 € per child)
– child birth benefit (one-time 829.86 € at birth)
Entitlement to family transfers is currently unconditional on income and applies up to 3 years of age of the child.
Child birth benefit is granted up to the third childbirth.

The eligibility for family transfers is tested against an assessed income defined as the gross taxable income of members of the family. If the family's assessed income is higher than 4 times the amount of their minimum subsistence level (MSL), the family transfers are not granted.

Tax credit for dependent children is not granted if the above-mentioned income condition is fulfilled.
Tax credit for dependent children in the amount of 21.41 € monthly per child.
Reduction of material need benefits Material need allowances consist of:
– basic material need benefit (MNB) varies from 61.60 € up to 216.10 € monthly, depending on the family structure.
– allowance for pregnant women and parent of children up to 1 year of age: 13.50 €
– activation and protection allowance: 63.07 €
– housing allowance: 55.80 € or 89.20 €, depending on the family structure		 Reduction of MNB (of all allowances) by 10%.
Family is eligible for MNB if their assessed income (net income from labour plus pensions) is below MSL of the family. MSL levels are:
– first adult 199.48 €
– jointly considered another person 139.16 €
– dependent children 91.06 €
Table A.1
Point estimates of probit model (pooled regression 2012–15).
Dependent variable ACTIVE Females Males
logGTW 0.314*** (0.043) 0.248*** (0.054)
logNY –0.201*** (0.018) –0.181*** (0.023)
EDU: Secondary 0.586*** (0.033) 0.626*** (0.039)
EDU: Tertiary 0.760*** (0.042) 0.843*** (0.051)
Parent with child under 3y. –2.159*** (0.037) 0.450*** (0.087)
Parent with child over 3y. 0.075** (0.029) 0.413*** (0.044)
Fam: Married –0.070* (0.036) –0.076* (0.045)
Fam: Divorced / Widowed 0.121*** (0.040) –0.002 (0.066)
Has working partner 0.229*** (0.034) 0.289*** (0.042)
Chronic disease –0.728*** (0.025) –1.162*** (0.032)
Student –2.042*** (0.038) –2.240*** (0.040)
Pensioner –2.465*** (0.034) –2.873*** (0.047)
Year 2013 –0.072** (0.030) 0.054 (0.038)
Year 2014 –0.103*** (0.030) 0.051 (0.038)
Year 2015 –0.107*** (0.030) 0.036 (0.038)
Constant 0.090 (0.367) 0.580 (0.479)
Observations 27 682 24 057
R2 pseudo 0.538 0.638

  1. Notes: Standard errors in parentheses, Reference categories for the dummies: Education (ref. Elementary), Family status (ref. Single), Year (ref. 2012).

  2. *

    p<0.1.

  3. **

    p<0.05.

  4. ***

    p<0.01.

Table A.2
Summary of the parameters used in the macro block of the model.
Parameter Value Description / Source
α 0.43 Share of labour in CES production function estimate (Bencik, 2008)
σ (0.48–1)/0.48 Transformed elasticity of substitution (Bencik, 2008)
β 0.99 Discount factor
λ 0.004 Job separation rate (Labour Market Developments in Europe 2013, EC, 2013)
ξ 0.8 Match elasticity of the unemployed (Zeleznik, 2012 or Nemec, 2013)
μ 0.05 Scaling factor of matching function – efficiency of the process (calibrated)
c 1.00 Vacancy posting costs (calibrated)
r 0.01 Quarterly interest rate – price of capital (calibrated)
τK 0.172 Effective corporate income tax rate (calibrated)
Table B.1-1
Simulated short-term effects in %.
SIC and HIC paid by Inequality
Fiscal effect Fiscal revenues PIT employees employers self-empl VAT CIT Fiscal expend Post VAT income GINI Kak wani
baseline, 2018 9 284 17 851 2 414 2 616 6 922 1 108 3 115 1 676 8 567 1 192 27.4 6.4
PIT – 1 p.p. increase in the standard rate 1.40 0.73 5.70 *** 0.00 0.00 0.00 −0.25 *** 0.00 0.00 −0 49 *** −0.12 0.24
PIT – one tax rate 4.11 2.14 16.76 *** 0.00 0.00 0.00 −0.73 *** 0.00 0.00 −1 44 *** −0.35 0.61
PIT – decreasing tax allowances 0.84 0.44 3 44 *** 0.00 0.00 0.00 −0.16 ** 0.00 0.00 −0 29 *** 0.00 −0.30
HIC – 1 p.p. increase in the rate paid by employers 1.76 0.92 0.00 0.00 2.69 *** 0.00 0.00 −1.34 0.00 0.00 0.00 0.00
HIC – 1 p.p. increase in the rate paid by employees 1.52 0.79 −1.50 *** 7.12 *** 0.00 0.00 −0.28 *** 0.00 0.00 −0.53 *** −0.08 −0.05
VAT – 1 p.p. increase in the standard rate 1.34 0.70 0.00 0.00 0.00 0.00 3.99 *** 0.00 0.00 −0.47 0.00 0.00
VAT – abolition of reduced rate 0.94 0.49 0.00 0.00 0.00 0.00 2.80 *** 0.00 0.00 −0.33 0.00 0.00
CIT – 1 p.p. increase in the rate 0.84 0.44 0.00 0.00 0.00 0.00 0.00 4.65 0.00 0.00 0.00 0.00
Reduction of family related transfers and credits 1.52 0.24 210 *** 0.00 0.00 0.05 −0.30 *** 0.00 −1 16*** −0.56 *** −0.20 0.16
Reduction of material need benefits 0.40 −0.02 0.00 0.00 0.00 0.00 −0.12 * 0.00 −0.48 *** −0.15 * 0.16 −0.03

  1. Notes: First row (baseline) represents direct output from the simulation model; monetary variables in mil. euros.

    Subsequent rows display changes in % from baseline values. In case of inequality measures the numbers express changes in percentage points.

    SIC – social insurance contributions, HIC – health insurance contributions, PIT – personal income tax, VAT – value added tax, CIT – corporate income tax.

  2. *, **, ***

    denote statistically significant difference between baseline and scenario at 10%, 5% and 1% levels, respectively. Standard errors are computed conventionally. Thus, the statistical significance reflects sampling error, rather than modelling uncertainty. Statistical significance is displayed for PIT, SIC&HIC, VAT, fiscal expenditures and disposable income. CIT is computed directly using the effective tax rate. Post-VAT income reflects households' disposable income minus VAT expenses.

Table B.1-2
Simulated behavioural effects in %.
SIC and HIC paid by Inequality
Fiscal effect Fiscal revenues PIT employees employers self-empl VAT CIT Fiscal expend Post VAT income GINI Kak wani
baseline, 2018 9 284 17 851 2 414 2 616 6 922 1 108 3 115 1 676 8 567 1 192 27.4 6.4
PIT – 1 p.p. increase in the standard rate 1.23 0.64 5.51 *** −0.12 −0.12 0.00 −0.28 *** 0.06 0.00 −0.55 *** −0.14 0.24
PIT – one tax rate 3.58 1.86 16.20 *** −0.34 *** −0.34 *** −0.22 −0.85 *** 0.17 0.00 −1.65 *** −0.41 0.68
PIT – decreasing tax allowances 0.81 0.43 3.45*** −0.01 −0.01 0.00 −0.16 ** 0.00 0.02 −0.30 *** 0.01 −0.30
HIC – 1 p.p. increase in the rate paid by employers 1.76 0.92 0.00 0.00 2.69 *** 0.00 0.00 −1.34 0.00 0.00 0.00 0.00
HIC – 1 p.p. increase in the rate paid by employees 1.29 0.68 −1 67 *** 6.96 *** −0.16 ** 0.00 −0.32 *** 0.08 0.03 −0.61 *** −0.07 −0.06
VAT – 1 p.p. increase in the standard rate 1.34 0.70 0.00 0.00 0.00 0.00 3.99 *** 0.00 0.00 −0.47 0.00 0.00
VAT – abolition of reduced rate 0.94 0.49 0.00 0.00 0.00 0.00 2.80 *** 0.00 0.00 −0.33 0.00 0.00
CIT – 1 p.p. increase in the rate 0.84 0.44 0.00 0.00 0.00 0.00 0.00 4.65 0.00 0.00 0.00 0.00
Reduction of family related transfers and credits 1.51 0.23 2 09 *** −0.01 −0.01 0.05 −0.30 *** 0.00 −1.16*** −0.56 *** −0.21 0.15
Reduction of material need benefits 0.79 0.10 0.01 0.23 *** 0.23 *** 0.00 −0.05 −0.12 −0.64 *** −0.05 0.03 0.00

  1. Notes: First row (baseline) represents direct output from the simulation model; monetary variables in mil. euros.

    Subsequent rows display changes in % from baseline values. In case of inequality measures the numbers express changes in percentage points.

    SIC – social insurance contributions, HIC – health insurance contributions, PIT – personal income tax, VAT – value added tax, CIT – corporate income tax.

  2. *, **, ***

    denote statistically significant difference between baseline and scenario at 10%, 5% and 1% levels, respectively. Standard errors are computed conventionally. Thus, the statistical significance reflects sampling error, rather than modelling uncertainty. Statistical significance is displayed for PIT, SIC&HIC, VAT, fiscal expenditures and disposable income. CIT is computed directly using the effective tax rate. Post-VAT income reflects households' disposable income minus VAT expenses.

Table B.1-3
Simulated long term effects in %.
SIC and HIC paid by Inequality
Fiscal effect Fiscal revenues PIT employees employers self-empl VAT CIT Fiscal expend Post VAT income GINI Kak wani
baseline, 2018 9 284 17 851 2 414 2 616 6 922 1 108 3 115 1 676 8 567 1 192 27.4 6.4
PIT – 1 p.p. increase in the standard rate 1.24 0.64 5.60 *** −0.07 −0.07 0.03 −0.26 *** −0.36 0.00 −0.52 *** −0.13 0.23
PIT – one tax rate 3.63 1.89 16.51 *** −0.17 ** −0.17 ** −0.12 −0.80 *** −1.12 0.01 −1.55 *** −0.40 0.67
PIT – decreasing tax allowances 0.84 0.45 3.52 *** 0.04 0.04 0.03 −0.15 ** −0.26 0.02 −0 27 *** 0.01 −0.30
HIC – 1 p.p. increase in the rate paid by employers 1.10 0.57 −0 87 *** −0.53 *** 215 *** −0.47 − 0.17 ** −0.08 0.00 −0 32*** −0.05 0.04
HIC – 1 p.p. increase in the rate paid by employees 1.32 0.70 −1 52*** 7.06 *** −0.06 0.03 −0.30 *** −0.59 0.03 −0.55 *** −0.07 −0.06
VAT – 1 p.p. increase in the standard rate 1.35 0.70 0.02 0.01 0.01 0.01 4.00 *** −0.05 0.00 −0.46 0.00 0.00
VAT – abolition of reduced rate 0.94 0.49 0.01 0.00 0.00 0.00 2.80 *** −0.02 0.00 −0.33 0.00 0.00
CIT – 1 p.p. increase in the rate 0.76 0.40 −0.14 −0.08 −0.08 −0.05 −0.03 4.96 0.00 −0.05 −0.01 0.00
Reduction of family related transfers and credits 1.48 0.21 2.02*** −0.05 −0.05 0.03 −0.31 *** 0.21 −1 16*** −0.58 *** −0.21 0.16
Reduction of material need benefits 0.60 0.00 −0.51 *** −0.09 −0.09 −0.34 −0.15 ** 1.79 −0.64 *** −0 24 *** 0.00 0.04

  1. Notes: First row (baseline) represents direct output from the simulation model; monetary variables in mil. euros.

    Subsequent rows display changes in % from baseline values. In case of inequality measures the numbers express changes in percentage points.

    SIC – social insurance contributions, HIC – health insurance contributions, PIT – personal income tax, VAT – value added tax, CIT – corporate income tax.

  2. *, **, ***

    denote statistically significant difference between baseline and scenario at 10%, 5% and 1% levels, respectively. Standard errors are computed conventionally. Thus, the statistical significance reflects sampling error, rather than modelling uncertainty. Statistical significance is displayed for PIT, SIC&HIC, VAT, fiscal expenditures and disposable income. CIT is computed directly using the effective tax rate. Post-VAT income reflects households' disposable income minus VAT expenses.

Table B.2-1
Simulated short-term effects in mil. EUR.
SIC and HIC paid by
Fiscal effect Fiscal revenues PIT employees employers self-empl VAT CIT Fiscal expend
re-scaled baseline, 2018; 13 096 22 278 2 829 2 822 7 465 1 195 5 393 2 575 9 182
PIT – 1 p.p. increase in the standard rate 147.8 147.8 161.09 0.00 0.00 0.00 −13.30 0.00 0.0
PIT – one tax rate 434.6 434.6 474.03 0.00 0.00 0.00 −39.38 0.00 0.0
PIT – decreasing tax allowances 88.7 88.7 97.33 0.00 0.00 0.00 −8.68 0.00 0.0
HIC – 1 p.p. increase in the rate paid by employers 166.4 166.4 0.00 0.00 200.97 0.00 0.00 −34.6 0.0
HIC – 1 p.p. increase in the rate paid by employees 143.4 143.5 −42.45 200.98 0.00 0.00 −15.04 0.00 0.1
VAT – 1 p.p. increase in the standard rate 245.6 245.6 0.00 0.00 0.00 0.00 245.59 * 0.00 0.0
VAT – abolition of reduced rate 172.2 172.2 0.00 0.00 0.00 0.00 172.21 * 0.00 0.0
CIT – 1 p.p. increase in the rate 119.8 119.8 0.00 0.00 0.00 0.00 0.00 119.8 0.0
Reduction of family related transfers and credits 136.8 44.1 59.52 0.00 0.00 0.64 −16.06 0.00 −92.7
Reduction of material need benefits 15.7 −6.7 0.00 0.00 0.00 0.00 −6.70 0.00 −22.4

  1. Notes: First row represents the re-scaled baseline values for fiscal variables; monetary variables in mil. euros. For VAT, baseline value is the estimated amount of VAT paid by households. Subsequent rows display difference in mil. euros compared to re-scaled baseline values.

    SIC – social insurance contrib., HIC – health insurance contrib., PIT – personal income tax, VAT – value added tax, CIT – corporate income tax.

  2. *

    For scenarios involving the change of VAT rate the baseline is rescaled to the total amount in the economy (6 149.8 mil. euros).

B.2-2
Simulated behavioural effects in mil. EUR.
SIC and HIC paid by
Fiscal effect Fiscal revenues PIT employees employers self-empl VAT CIT Fiscal expend
re-scaled baseline, 2018 13 096 22 278 2 829 2 822 7 465 1 195 5 393 2 575 9 182
PIT – 1 p.p. increase in the standard rate 130.1 130.1 155.94 −3.39 −8.94 −0.06 −14.99 1.5 0.0
PIT – one tax rate 378.9 379.1 458.26 −9.57 −25.31 −2.68 −45.98 4.4 0.2
PIT – decreasing tax allowances 86.8 87.8 97.51 −0.28 −0.74 0.00 −8.87 0.1 0.9
HIC – 1 p.p. increase in the rate paid by employers 166.4 166.4 0.00 0.00 200.97 0.00 0.00 −34.6 0.0
HIC – 1 p.p. increase in the rate paid by employees 120.7 121.9 −47.32 196.26 −11.58 −0.03 −17.45 2.0 1.2
VAT – 1 p.p. increase in the standard rate 245.6 245.6 0.00 0.00 0.00 0.00 245.59 * 0.0 0.0
VAT – abolition of reduced rate 172.2 172.2 0.00 0.00 0.00 0.00 172.21 * 0.0 0.0
CIT – 1 p.p. increase in the rate 119.8 119.8 0.00 0.00 0.00 0.00 0.00 119.8 0.0
Reduction of family related transfers and credits 135.3 42.6 59.04 −0.28 −0.74 0.63 −16.20 0.1 −92.7
Reduction of material need benefits 48.6 18.3 0.32 6.44 17.33 0.00 −2.83 −3.0 −30.3

  1. Notes: First row represents the re-scaled baseline values for fiscal variables; monetary variables in mil. euros. For VAT, baseline value is the estimated amount of VAT paid by households. Subsequent rows display difference in mil. euros compared to re-scaled baseline values.

    SIC – social insurance contrib., HIC – health insurance contrib., PIT – personal income tax, VAT – value added tax, CIT – corporate income tax.

  2. *

    For scenarios involving the change of VAT rate the baseline is rescaled to the total amount in the economy (6 149.8 mil. euros).

Table B.2-3
Simulated long term effects in mil. EUR.
SIC and HIC paid by
Fiscal effect Fiscal revenues PIT employees employers self-empl VAT CIT Fiscal expend
re-scaled baseline, 2018 13 096 22 278 2 829 2 822 7 465 1 195 5 393 2 575 9 182
PIT – 1 p.p. increase in the standard rate 128.5 128.5 158.53 −1.90 −5.04 0.31 −14.09 −9.3 0.0
PIT – one tax rate 375.7 375.9 467.12 −4.91 −13.01 −1.43 −43.02 −28.8 0.2
PIT – decreasing tax allowances 88.2 89.1 99.69 1.02 2.69 0.35 −8.07 −6.6 0.9
HIC – 1 p.p. increase in the rate paid by employers 103.8 103.9 −24.65 −14.94 160.34 −5.67 −9.03 −2.2 0.1
HIC – 1 p.p. increase in the rate paid by employees 119.3 120.7 −43.00 199.11 −4.65 0.31 −15.96 −15.1 1.4
VAT – 1 p.p. increase in the standard rate 246.0 246.0 0.46 0.27 0.72 0.08 245.80 * −1.3 0.0
VAT – abolition of reduced rate 172.4 172.4 0.17 0.10 0.28 0.04 172.28 * −0.5 0.0
CIT – 1 p.p. increase in the rate 113.2 113.3 −3.90 −2.35 −6.19 −0.62 −1.44 127.8 0.0
Reduction of family related transfers and credits 133.8 41.1 57.26 −1.35 −3.56 0.35 −16.86 5.3 −92.7
Reduction of material need benefits 40.7 10.4 −14.47 −2.58 −6.39 −4.09 −8.23 46.2 −30.3

  1. Notes: First row represents the re-scaled baseline values for fiscal variables; monetary variables in mil. euros. For VAT, baseline value is the estimated amount of VAT paid by households. Subsequent rows display difference in mil. euros compared to re-scaled baseline values.

    SIC – social insurance contrib., HIC – health insurance contrib., PIT – personal income tax, VAT – value added tax, CIT – corporate income tax.

  2. *

    For scenarios involving the change of VAT rate the baseline is rescaled to the total amount in the economy (6 149.8 mil. euros).

Table B.3
Changes in probabilities of being economically active (in p.p.).
All Age Parent with child up to 3 years
25-50, 25-50,
15-24 female male 50+ Female Male
baseline probabilities, 2018 64.06 35.13 74.69 92.88 50.17 26.56 97.24
PIT – 1 p.p. increase in the standard rate −0.014 −0.007 −0.008 −0.006 −0.025 −0.017 −0.002
PIT – one tax rate −0.043 −0.024 −0.024 −0.020 −0.077 −0.051 −0.007
PIT – decreasing tax allowances −0.012 −0.022 −0.014 −0.007 −0.010 −0.020 −0.003
HIC – 1 p.p. increase in the rate paid by employers 0.000 0.000 0.000 0.000 0.000 0.000 0.000
HIC – 1 p.p. increase in the rate paid by employees −0.027 −0.035 −0.036 −0.013 −0.027 −0.063 −0.007
VAT – 1 p.p. increase in the standard rate −0.002 −0.004 −0.004 0.001 −0.002 −0.010 0.000
VAT – abolition of reduced rate −0.001 −0.002 −0.003 0.002 −0.001 −0.006 0.000
CIT – 1 p.p. increase in the rate 0.000 0.000 0.000 0.000 0.000 0.000 0.000
Reduction of family related transfers and credits 0.008 0.021 0.016 0.005 0.001 0.073 0.014
Reduction of material need benefits 0.093 0.086 0.176 0.064 0.065 0.107 0.051

  1. Notes: First row represents probabilities of being economically active simulated by the model. Subsequent rows express the changes in percentage points from baseline probabilities for different population groups.

Table B.4
Long-term changes in macroeconomic indicators.
employment (PP) work intensity (P.P.) eff. labour (P.P.) gross wages (%) net wages (%) outPut (%) unemP. rate (P.P.)
PIT – 1 p.p. increase in the standard rate −0.02 −0.03 −0.08 0.05 −0.39 −0.08 0.02
PIT – one tax rate −0.06 −0.09 −0.22 0.14 −1.18 −0.23 0.06
PIT – decreasing tax allowances −0.02 0.00 −0.01 0.04 −0.32 −0.01 0.02
HIC – 1 p.p. increase in the rate paid by employers 0.00 −0.01 −0.02 −0.45 −0.38 −0.03 0.00
HIC – 1 p.p. increase in the rate paid by employees −0.03 −0.03 −0.08 0.08 −0.48 −0.08 0.03
VAT – 1 p.p. increase in the standard rate 0.00 0.00 0.00 0.01 0.01 0.00 0.00
VAT – abolition of reduced rate 0.00 0.00 0.00 0.01 0.01 0.00 0.00
CIT – 1 p.p. increase in the rate 0.00 0.00 0.00 0.00 0.00 0.00 0.00
Reduction of family related transfers and credits 0.00 0.00 0.00 −0.07 −0.06 −0.04 0.00
Reduction of material need benefits 0.01 0.00 0.00 −0.03 −0.16 0.00 −0.01

  1. Notes: employment – employment rate, work intensity – intensive margin response, effective labour – total labour supply, gross wages – gross wages of working population, net wages – gross wages of working population net of social and health insurance contributions, output – GDP.

Download links

A two-part list of links to download the article, or parts of the article, in various formats.

Downloads (link to download the article as PDF)

Download citations (links to download the citations from this article in formats compatible with various reference manager tools)

Open citations (links to open the citations from this article in various online reference manager services)