我的代码如下：
\documentclass{book}
\usepackage{amsmath}
\usepackage{wasysym} %ch06 - $\currency$
\usepackage{multirow} %ch10 - table4
\usepackage{amssymb} %ch12 - \thicksim
\usepackage[round,authoryear,comma,longnamesfirst]{natbib}
\begin{document}
\makeatletter
\renewenvironment{thebibliography}[1]{%
\chapter*{REFERENCES}%
\markboth{References}{References}%
\addcontentsline{toc}{chapter}{\refname}%
\small\list{}{%
\leftmargin 1em\itemindent -1em\parsep \z@
\itemsep\z@%
}}%
{\endlist}%
\makeatother
\begin{thebibliography}{}
\bibitem[\protect\citeauthoryear{Ahmed and Rogers}{Ahmed and
Rogers}{1995}]{Ahmed1995}
Ahmed, S. and J.~H. Rogers (1995).
\newblock Government budget deficits and trade deficits: Are present value
constraints satisfied in long-term data?
\newblock {\em Journal of Monetary Economics\/}~{\em 36\/}(2), 351--374.
\bibitem[\protect\citeauthoryear{Alesina and Ardagna}{Alesina and Ardagna}{1998}]{Ardagna1998}
Alesina, A. and S. Ardagna (1998). Tales of fiscal adjustment. \textit{Economic Policy}~{\em 13\/}(27), 489--585.
%\bibitem[\protect\citeauthoryear{Ahmed and Rogers}{Ahmed and
% Rogers}{1995}]{Ahmed1995}
%Ahmed, S. and J.~H. Rogers (1995).
%\newblock Government budget deficits and trade deficits are present value
% constraints satisfied in long-term data?
%\newblock {\em Journal of Monetary Economics\/}~{\em 36\/}(2), 351--374.
\bibitem[\protect\citeauthoryear{Alesina and Ardagna}{Alesina and
Ardagna}{2010}]{Alesina2010}
Alesina, A. and S.~Ardagna (2010).
\newblock Large changes in fiscal policy: Taxes versus spending.
\newblock In {\em Tax Policy and the Economy,} Volume 24, pp.\
35--68. National Bureau of Economic Research.
\bibitem[\protect\citeauthoryear{Alesina and Ardagna}{Alesina and
Ardagna}{2013}]{Alesina2013}
Alesina, A. and S.~Ardagna (2013).
\newblock The design of fiscal adjustments.
\newblock {\em Tax Policy and the Economy\/}, Volume 27, pp., 19--68.
\bibitem[\protect\citeauthoryear{Alesina, Ardagna, and Galasso}{Alesina
et~al.}{2010}]{Alesina2010b}
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\newblock In A.~Alesina and F.~Giavazzi (Eds.), {\em Europe and the Euro},
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Schiantarelli}{Alesina et~al.}{2002}]{Alesina2002}
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\newblock {\em American Economic Review\/}~{\em 92\/}(3), 571--589.
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et~al.}{2006}]{Alesina2006}
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\newblock {\em IMF Staff Papers\/}~{\em 53}, 1--49.
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Miano}{Alesina et~al.}{2016}]{Alesina2016a}
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\newblock Is it the ``how" or the ``when" that matters in fiscal adjustments?
\newblock IMF Economic Review 66(1), 144--188.
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Paradisi}{Alesina et~al.}{2015}]{Alesina2015}
Alesina, A., O.~Barbiero, C.~Favero, F.~Giavazzi, and M.~Paradisi (2015).
\newblock Austerity in 2009-13.
\newblock {\em Economic Policy\/}~{\em 30\/}(83), 383--437.
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Paradisi}{Alesina et~al.}{2017}]{Alesina2017}
Alesina, A., O.~Barbiero, C.~Favero, F.~Giavazzi, and M.~Paradisi (2017, May).
\newblock The effects of fiscal consolidations: Theory and evidence.
\newblock Working Paper 23385, National Bureau of Economic Research.
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et~al.}{2012}]{Alesina2012b}
Alesina, A., D.~Carloni, and G.~Lecce (2013).
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Alesina, A., C. Favero, and F. Giavazzi (2015). The output effect of fiscal
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et~al.}{2005}]{Alesina2005}
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\newblock Work and leisure in the United States and Europe: Why so different?
\newblock {\em NBER Macroeconomics Annual\/}~{\em 20}, 1--64.
\bibitem[\protect\citeauthoryear{Alesina and Passalacqua}{Alesina and
Passalacqua}{2016}]{Alesina2016}
Alesina, A. and A.~Passalacqua (2016).
\newblock The political economy of government debt.
\newblock In J.~B. Taylor and H.~Uhlig (Eds.), {\em Handbook of
Macroeconomics}, Volume~2, pp.\ 2599--2651. Elsevier.
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Perotti}{1996}]{Alesina1996}
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\newblock Fiscal adjustments in OECD countries: \text{Composition} and macroeconomic
effects.
\newblock IMF Staff Papers 44, 210--248.
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Perotti}{1997}]{Alesina1997}
Alesina, A. and R.~Perotti (1997).
\newblock The welfare state and competitiveness.
\newblock {\em American Economic Review\/}~{\em 87\/}(5), 921--939.
\bibitem[\protect\citeauthoryear{Alesina, Perotti, Tavares, Obstfeld, and
Eichengreen}{Alesina et~al.}{1998}]{Alesina1998}
Alesina, A., R.~Perotti, J.~Tavares, M.~Obstfeld, and B.~Eichengreen (1998).
\newblock The political economy of fiscal adjustments.
\newblock {\em Brookings Papers on Economic Activity\/}~{\em 1998\/}(1),\break 197--266.
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Caselli}{2014}]{Ardagna2014}
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\newblock The political economy of the Greek debt crisis: A tale of two
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\newblock {\em American Economic Journal: Macroeconomics\/}~{\em 6\/}(4),
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Gorodnichenko}{2012b}]{Auerbach2012a}
Auerbach, A.~J. and Y.~Gorodnichenko (2012).
\newblock Measuring the output responses to fiscal policy.
\newblock {\em American Economic Journal: Economic Policy\/}~{\em 4\/}(2),
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Gorodnichenko}{2012a}]{Auerbach2012}
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\newblock Fiscal multipliers in recession and expansion.
\newblock In {\em Fiscal Policy after the Financial Crisis},
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Gorodnichenko}{2013}]{Auerbach2013}
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\newblock Output spillovers from fiscal policy.
\newblock {\em American Economic Review\/}~{\em 103\/}(3), 141--146.
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\newblock Structural reform Australian-style: Lessons for others?
\newblock Technical report, Organisation for Economic Co-operation and Development.
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Matthes}{2015}]{Barnichon2015}
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\newblock Stimulus versus austerity: The asymmetric government spending
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\newblock CEPR Discussion Paper 10584.
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\newblock Bargaining in legislatures.
\newblock {\em The American Political Science Review\/}~{\em 83\/}(4),
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\bibitem[\protect\citeauthoryear{Barro}{Barro}{1981}]{Barro1981}
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\newblock Output effects of government purchases.
\newblock {\em Journal of Political Economy\/}~{\em 89\/}(6), 1086--1121.
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\newblock {\em Macroeconomics}.
\newblock Wiley. 2
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\newblock Economic growth in East Asia before and after the financial crisis.
\newblock Working paper 8330, National Bureau of Economic Research.
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Redlick}{2011}]{Barro2011}
Barro, R.~J. and C.~J. Redlick (2011).
\newblock Macroeconomic effects from government purchases and taxes.
\newblock {\em The Quarterly Journal of Economics\/}~{\em 126\/}(1), 51--102.
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Coate}{2008}]{Battaglini2008}
Battaglini, M. and S.~Coate (2008, March).
\newblock A dynamic theory of public spending, taxation, and debt.
\newblock {\em American Economic Review\/}~{\em 98\/}(1), 201--236.
\bibitem[\protect\citeauthoryear{Baxter and King}{Baxter and
King}{1993}]{Baxter1993}
Baxter, M. and R.~G. King (1993, June).
\newblock Fiscal policy in general equilibrium.
\newblock {\em American Economic Review\/}~{\em 83\/}(3), 315--334.
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\newblock Multipliers of unexpected increases in defense spending: An empirical
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\newblock {\em Journal of Economic Dynamics and Control\/}~{\em 57\/}(C),
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et~al.}{2016}]{Bick2016}
Bick, A., B.~Bruggemann, and N.~Fuchs-Schundeln (2016).
\newblock Hours worked in Europe and the US: New data, new answers.
\newblock IZA Discussion Paper 10179, Institute for the Study of Labor (IZA).
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Blanchard, O.~J. and D.~Leigh (2014, June).
\newblock Learning about fiscal multipliers from growth forecast errors.
\newblock {\em IMF Economic Review\/}~{\em 62\/}(2), 179--212.
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Perotti}{2002}]{Blanchard2002}
Blanchard, O.~J. and R.~Perotti (2002).
\newblock An empirical characterization of the dynamic effects of changes in
government spending and taxes on output.
\newblock {\em The Quarterly Journal of Economics\/}~{\em 117\/}(4),
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Blanchard, O.~J. and M.~Watson (1986).
\newblock Are business cycles all alike?
\newblock In R.~J. Gordon (Ed.), {\em The American Business Cycle: Continuity
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\bibitem[\protect\citeauthoryear{Bloom}{Bloom}{2009}]{Bloom2009}
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\newblock The impact of uncertainty shocks.
\newblock {\em Econometrica\/}~{\em 77\/}(3), 623--685.
\bibitem[\protect\citeauthoryear{Blundell, Bozio, and Laroque}{Blundell
et~al.}{2011}]{Blundell2011}
Blundell, R., A.~Bozio, and G.~Laroque (2011, May).
\newblock Labor supply and the extensive margin.
\newblock {\em American Economic Review\/}~{\em 101\/}(3), 482--486.
\bibitem[\protect\citeauthoryear{Bohn}{Bohn}{1991}]{Bohn1991}
Bohn, H. (1991).
\newblock Budget balance through revenue or spending adjustments?
\newblock {\em Journal of Monetary Economics\/}~{\em 27\/}(3), 333--359.
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Drazen}{2008}]{Brender2008}
Brender, A. and A.~Drazen (2008, December).
\newblock How do budget deficits and economic growth affect reelection
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\newblock {\em American Economic Review\/}~{\em 98\/}(5), 2203--2220.
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Buchanan, J.~M. and R.~E. Wagner (1977).
\newblock {\em Democracy in Deficit: The Political Legacy of Lord Keynes}.
\newblock New York: Academic Press.
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Burnside, C., M.~Eichenbaum, and J.~D.~M. Fisher (2004, March).
\newblock Fiscal shocks and their consequences.
\newblock {\em Journal of Economic Theory\/}~{\em 115\/}(1), 89--117.
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Caldara, D. and C.~Kamps (2017).
\newblock The analytics of SVARS: A unified framework to measure fiscal
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\newblock {\em Review of Economic Studies\/} 84(3), 1015--1040.
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Goudswaard}{2009}]{Caminada2009}
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\newblock Effectiveness of poverty reduction in the EU: A descriptive analysis.
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\newblock Government employment expenditure and the effects of fiscal policy
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et~al.}{2011}]{Chang2011}
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\newblock Interpreting labor supply regressions in a model of full- and
part-time work.
\newblock {\em American Economic Review\/}~{\em 101\/}(3), 476--481.
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et~al.}{2011}]{Chetty2011}
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\newblock Does state fiscal relief during recessions increase employment?
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\newblock {\em American Economic Journal: Economic Policy\/}~{\em 4\/}(3),\break
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et~al.}{2011}]{Christiano2011}
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\newblock When is the government spending multiplier large?
\newblock {\em Journal of Political Economy\/}~{\em 119\/}(1), 78--121.
\end{thebibliography}
\end{document}
如果我删除最后一项，那么它就可以正常工作，请指出我做错了什么？如果错误很愚蠢，请原谅我……
请注意，我在 Windows 系统上使用 MikTeX v2.9....
答案1
没有错误消息，只有以下警告消息：
Package natbib Warning: Citation `Alesina2015' multiply defined.
...
Package natbib Warning: There were multiply defined citations.
[3] (uu.aux
Package natbib Warning: Citation(s) may have changed.
(natbib) Rerun to get citations correct.
基本上，您有两个具有相同引用键的条目，即Alesina2015。
如何解决这个问题？
打开 bib 文件，找到带有键 的条目
Alesina2015，并修改其中一个或多个键以使其唯一。假设 bib 文件恰好包含两个带有键 的条目Alesina2015，并且假设您将键更改为Alesina2015uu和Alesina2015vv。接下来，检查
\cite您的 tex 文档中当前提及的所有 -like 指令Alesina2015。确定哪些应该指向Alesina2015a，哪些应该指向Alesina2015b，并执行所需的修改。一旦 bib 文件中的条目被更正并且指令的参数
\cite被更新，请再重新运行 LaTeX、BibTeX 和 LaTeX 两次以完全传播所有更改。要验证先前与参考书目相关的错误是否已消失，请打开日志文件并尝试查找字符串
Package natbib Warning: There were multiply defined citations.如果找不到这样的字符串，则表示您已成功修复问题。