Muss am Montag meine Projektarbeit abgeben und bis dahin muss noch einiges geändert werden

Für das Literaturverzeichnis benutzte ich einen eigenen biblatex Stil. Ich habe das Problem, dass ich mehrere Quellen vom gleichen Autor hab und im Verzeichnis ein Wiederholungsstrich steht. Stehen muss aber "Amazon (2011)"und "Amazon (2011a)" etc.
Hier mein Stil:
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{\usebibmacro{name:last-first}{#1}{#4}{#5}{#7}}% \ifblank{#3#5} {} {\usebibmacro{name:revsdelim}}% \else \iffirstinits {\usebibmacro{name:last-first}{#1}{#4}{#5}{#7}} {\usebibmacro{name:last-first}{#1}{#4}{#5}{#7}}% \fi \usebibmacro{name:andothers}} \renewcommand*{\newunitpunct}{\addcomma\space} \renewcommand*{\multinamedelim}{\addslash} \renewcommand*{\finalnamedelim}{\addslash} \renewcommand*{\multilistdelim}{\addslash} \renewcommand*{\labelnamepunct}{\addcolon\space} \renewcommand*{\finentrypunct}{\space} \defbibenvironment{bibliography} {\list {\printfield[labelnumberwidth]{labelnumber}} {\setlength{\labelwidth}{\labelnumberwidth}% \setlength{\leftmargin}{\labelwidth}% \setlength{\labelsep}{\biblabelsep}% \addtolength{\leftmargin}{\labelsep}% \setlength{\itemsep}{\bibitemsep}% \setlength{\parsep}{\bibparsep}}% \renewcommand*{\makelabel}[1]{\hss##1}} {\endlist} {\item} \defbibenvironment{shorthands} {\list {\printfield[shorthandwidth]{shorthand}} {\setlength{\labelwidth}{\shorthandwidth}% \setlength{\leftmargin}{\labelwidth}% \setlength{\labelsep}{\biblabelsep}% \addtolength{\leftmargin}{\labelsep}% \setlength{\itemsep}{\bibitemsep}% \setlength{\parsep}{\bibparsep}% \renewcommand*{\makelabel}[1]{\hss##1}}} {\endlist} {\item} \DeclareBibliographyDriver{online}{% \usebibmacro{bibindex}% \usebibmacro{begentry}% \usebibmacro{author/editor+others/translator+others}% \setunit{\labelnamepunct}\newblock \printfield{title} \newunit \printlist{language}% \newunit\newblock \usebibmacro{byauthor}% \newunit\newblock \usebibmacro{byeditor+others}% \newunit\newblock \printfield{version}% \newunit \printfield{note}% \newunit\newblock \printlist{organization}% \newunit\newblock \usebibmacro{url+urldate} \newunit\newblock \newunit\newblock \usebibmacro{addendum+pubstate}% \newunit\newblock \usebibmacro{pageref}% \usebibmacro{finentry}} \DeclareBibliographyDriver{incollection}{% \usebibmacro{bibindex}% \usebibmacro{begentry}% 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\setunit{\addcolon\space} \printfield{title} \newunit \printlist{language}% \newunit\newblock \usebibmacro{byauthor}% \newunit\newblock \usebibmacro{bytranslator+others}% \newunit\newblock \printfield{version}% \newunit\newblock \usebibmacro{in:}% \usebibmacro{journal} \newunit\newblock \usebibmacro{volume+number}% \usebibmacro{note+pages}% \newunit\newblock \iftoggle{bbx:isbn} {\printfield{issn}} {}% \newunit\newblock \usebibmacro{doi+eprint+url}% \newunit\newblock \usebibmacro{addendum+pubstate}% \newunit\newblock \usebibmacro{pageref}% \usebibmacro{finentry}} \DeclareBibliographyDriver{book}{% \usebibmacro{bibindex}% \usebibmacro{begentry}% \usebibmacro{author/editor+others/translator+others}% \setunit{\labelnamepunct}\newblock \usebibmacro{maintitle+title}% \newunit \printlist{language}% \newunit\newblock \usebibmacro{byauthor}% \newunit\newblock \usebibmacro{byeditor+others}% \newunit\newblock \printfield{edition}% \newunit \iffieldundef{maintitle} {\printfield{volume}% \printfield{part}} {}% \newunit \printfield{volumes}% \newunit\newblock \usebibmacro{series+number}% \newunit\newblock \printfield{note}% \newunit\newblock \usebibmacro{publisher+location+date}% \newunit\newblock \usebibmacro{chapter+pages}% \newunit \printfield{pagetotal}% \newunit\newblock \iftoggle{bbx:isbn} {\printfield{isbn}} {}% \newunit\newblock \usebibmacro{doi+eprint+url}% \newunit\newblock \usebibmacro{addendum+pubstate}% \newunit\newblock \usebibmacro{pageref}% \usebibmacro{finentry}} \DeclareBibliographyDriver{book}{% \usebibmacro{bibindex}% \usebibmacro{begentry}% \usebibmacro{author/editor+others/translator+others}% \setunit{\addcolon\space} \usebibmacro{maintitle+title}% \newunit \printlist{language}% \newunit\newblock \usebibmacro{byauthor}% \newunit\newblock \usebibmacro{byeditor+others}% \newunit\newblock \usebibmacro{edition}% \newunit \iffieldundef{maintitle} {\printfield{volume}% \printfield{part}} {}% \newunit \printfield{volumes}% \newunit\newblock 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\setunit*{\addspace}}% \usebibmacro{year}} \newbibmacro*{volume+number}{% \printfield{volume}% \setunit*{\adddot}% \printtext{Jg.} \newunit \printtext{Nr. } \printfield{number}} \renewbibmacro*{author}{% \ifthenelse{\ifuseauthor\AND\NOT\ifnameundef{author}} {\ifthenelse{\iffieldequals{fullhash}{\bbx@lasthash}\AND \NOT\iffirstonpage\AND \(\NOT\boolean{bbx@inset}\OR \iffieldequalstr{entrysetcount}{1}\)} {\bibnamedash} {\usebibmacro{bbx:savehash}% \printnames{author}% \iffieldundef{authortype} {\setunit{\addspace}} {\setunit{\addcomma\space}}}% \iffieldundef{authortype} {} {\usebibmacro{authorstrg}% \setunit{\addspace}}}% {\global\undef\bbx@lasthash \usebibmacro{labeltitle}% \setunit*{\addspace}}% \usebibmacro{year}} \renewbibmacro*{note+pages}{% \printfield{note}% \setunit{\bibpagespunct}% \printfield{pages}% \newunit} \newbibmacro*{year}{% {\printtext[parens]{\printfield{year}}}} \newbibmacro*{edition}{% \iffieldequalstr{edition}{1} {} {\printfield{edition}} } \endinput
Vielen Dank!