我几天来一直在寻找解决问题的方法：
我使用 biblax 和 apa 格式。如果同一年有多个参考文献来自同一作者，则有一个选项。然后在年份后插入一个字母。我的问题是，不仅当参考文献来自同一作者时才会插入字母，而且无论作者是谁，只有在同一年才会插入字母。
我的文件：
\documentclass[11pt,a4paper,twoside]{report}
\usepackage[ngerman]{babel} %
%\usepackage{fancyhdr}
%\usepackage{hyperref}
\usepackage{csquotes}
\usepackage[ style=apa,
url=false,
doi=false,
isbn=false,
backend=biber,
hyperref=false,
eprint=false,
babel=other
]{biblatex}
\addbibresource{C:/Users/Konsi/Documents/Studium/test.bib} %ort der bib %
%\bibliography{C:/Users/Konsi/Documents/Studium/test.bib} %ort der bib %
\DeclareLanguageMapping{german}{german-apa}
\DefineBibliographyStrings{german}{andothers={et\ al\adddot}}
\begin{document}
\parencite{Billard2001}\\
\parencite{Wolpert2001487}
\printbibliography
\end{document}
然后我遇到了第一个问题：如果我第一次使用 latex->biber->latex->latex 编译此文件，则.bbl无法生成文件。因此，我将样式更改为 authoryear，latex->biber->latex->latex，.bbl文件已生成。我将样式改回apa，apa除了年份后面的字母外，一切都符合要求。
我的.bib是：
% This file was created with JabRef 2.7.2.
% Encoding: Cp1252
@ARTICLE{Billard2001,
author = {Billard, Aude},
title = {Learning motir skills by imitation: A biologically inspired robotiv
model},
journal = {Cybernetics and Systems},
year = {2001},
volume = {32},
pages = {155-193},
number = {1-2},
doi = {10.1080/019697201300001849},
eprint = {http://www.tandfonline.com/doi/pdf/10.1080/019697201300001849},
timestamp = {2012.07.08},
url = {http://www.tandfonline.com/doi/abs/10.1080/019697201300001849}
}
@ARTICLE{Wolpert2001487,
author = {Daniel M Wolpert and Zoubin Ghahramani and J.Randall Flanagan},
title = {Perspectives and problems in motor learning},
journal = {Trends in Cognitive Sciences},
year = {2001},
volume = {5},
pages = {487 - 494},
number = {11},
doi = {10.1016/S1364-6613(00)01773-3},
issn = {1364-6613},
keywords = {movement},
timestamp = {2012.07.07},
url = {http://www.sciencedirect.com/science/article/pii/S1364661300017733}
}
有人能帮帮我吗？第二个问题可能是由第一个问题引起的，但如果是这样，我该如何编译style=apa？
多谢！
编辑：使用的版本是（我不太确定，哪些有用，哪些没用）：缺少apa.dbx。这可能是个问题吗？我biblatex-apa使用 MiKTeX 2.9 包管理器安装了该包。
*File List*
report.cls 2007/10/19 v1.4h Standard LaTeX document class
size11.clo 2007/10/19 v1.4h Standard LaTeX file (size option)
babel.sty 2008/07/08 v3.8m The Babel package
bblopts.cfg 2006/07/31 v1.0 MiKTeX 'babel' configuration
ngermanb.ldf 2008/07/06 v2.6n new German support from the babel system
csquotes.sty 2011/10/22 v5.1d context-sensitive quotations
etoolbox.sty 2011/01/03 v2.1 e-TeX tools for LaTeX
etex.sty 1998/03/26 v2.0 eTeX basic definition package (PEB)
keyval.sty 1999/03/16 v1.13 key=value parser (DPC)
csquotes.def 2011/10/22 v5.1d csquotes generic definitions
csquotes.cfg
biblatex.sty 2012/07/01 v2.0 programmable bibliographies (PK/JW/AB)
biblatex2.sty 2012/07/01 v2.0 programmable bibliographies (biber) (PK/JW/AB)
kvoptions.sty 2010/12/23 v3.10 Keyval support for LaTeX options (HO)
ltxcmds.sty 2011/04/18 v1.20 LaTeX kernel commands for general use (HO)
kvsetkeys.sty 2011/04/07 v1.13 Key value parser (HO)
infwarerr.sty 2010/04/08 v1.3 Providing info/warning/message (HO)
etexcmds.sty 2011/02/16 v1.5 Prefix for e-TeX command names (HO)
ifluatex.sty 2010/03/01 v1.3 Provides the ifluatex switch (HO)
logreq.sty 2010/08/04 v1.0 xml request logger
logreq.def 2010/08/04 v1.0 logreq spec v1.0
ifthen.sty 2001/05/26 v1.1c Standard LaTeX ifthen package (DPC)
url.sty 2006/04/12 ver 3.3 Verb mode for urls, etc.
blx-dm.def
apa.dbx
biblatex-dm.cfg
blx-compat.def 2012/07/01 v2.0 biblatex compatibility (PK/JW/AB)
biblatex.def
standard.bbx 2012/07/01 v2.0 biblatex bibliography style (PK/JW/AB)
apa.bbx 2012/07/01 v5.0 APA biblatex references style
apa.cbx 2012/07/01 5.0 APA biblatex citation style
biblatex.cfg
german.lbx 2012/07/01 v2.0 biblatex localization (PK/JW/AB)
german-apa.lbx 2012/07/01 v5.0 APA biblatex localisation
ngerman.lbx 2012/07/01 v2.0 biblatex localization (PK/JW/AB)
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