\chapter{Standard Subspaces}

\cite{Longo2008}
\cite{Neeb2017}

\section{Test}
\begin{definition}{Symplectic Complement}{abc}
  test
  \nomenclature{$X$}{a Banach space, see \cref{definition:abc} asdf asdfasdf askdfj askdfj akdjf askdjf aksdfj aksdjfk asdjfksajf kasjdfkasjkfjsa kjsd ksjfaksjfksdjf}
\end{definition}
\begin{lemma}{Important}{xxx}
  test
\end{lemma}

\cref{lemma:xxx}
test

\section{Test}
\begin{definition}{cyclic, separating}{}
  test
\end{definition}
