The answer really depends on how you have set up your document and how you create your bibliogrphy etc (are you using bibtex, biblatex, ...?).

Any way one solution, which may or may not be appropriate is to add the following to your preamble:

\makeatletter
\def\thebibliography#1{%
  \c@chapter\z@ \c@section\z@\let\chaptername\relax
  \section*{References}\list
  {}{\settowidth\labelwidth{}\leftmargin\labelwidth
  \advance\leftmargin\labelsep
  \itemsep\z@\parsep\z@\topsep\z@\parskip\z@
  \usecounter{enumi}}
  \def\newblock{\hskip .11em plus .33em minus .07em}
  \sloppy\clubpenalty4000\widowpenalty4000
  \sfcode`\.=1000\relax}
\makeatletter


Actually, this solution makes the bibliography more compact, which you mightn't like.

Another solution, that it closer is spirit to what you tried, is to modify \bibitem. If you look at the definition of \bibitem (using, for example, \show), you will see that it calls \@bibtem and this is where the \item command comes from. Hence, you can get what you want with the following:

\makeatletter
\def\@bibitem#1{\item[]%
    \if@filesw\immediate\write\@auxout{\string \bibcite {#1}{\the\value{\@listctr }}}\fi\ignorespaces}
\makeatletter


The difference between these two approaches is the indentation of the bibliography entries. The first attempt produces



whereas the second gives you



The first approach is the more robust and the second may have unintended side-effects, not least because it doesn't cater for the optional argument that \bibitem accepts.

Remove numbers in bibliography
I'm just wondering some Questions (actually book request) are closed ( Good book for beginning android development ) and some questions are not closed (  Best book / resources for learning iOS programming? )?

Is there any specific reason? Or just it was overlooked by the community?

Update

The second question is closed now
