\begin{thebibliography}{1}
\providecommand{\natexlab}[1]{#1}
\providecommand{\url}[1]{\texttt{#1}}
\expandafter\ifx\csname urlstyle\endcsname\relax
  \providecommand{\doi}[1]{doi: #1}\else
  \providecommand{\doi}{doi: \begingroup \urlstyle{rm}\Url}\fi

\bibitem[MacFarlane(2019)]{commonmark}
{\sc MacFarlane}, J.
\newblock \emph{CommonMark Spec} [online]. 2019. [cit.~2020-03-22].
\newblock Dostupn{\'{e}}~z: \url{{https://spec.commonmark.org/}}.

\end{thebibliography}