% complile with »pdflatex«
\documentclass[tikz,convert=pdf2svg]{standalone}
\usetikzlibrary{calc,intersections}
\begin{document}
 \begin{tikzpicture}
  \pgfmathsetmacro{\radius}{3.9}
  \coordinate (A') at (53:\radius+1);
  \coordinate (C) at (88:\radius);
  \coordinate (D) at (27:\radius);
  \coordinate (E') at ($(C) +(-52:\radius+1)$);
  \coordinate (F) at (0,0);
  \path[draw, name path=lineCD] (C) to[bend left=31] (D);
  \path[draw, name path=lineFD] (F) to[bend right=29] (D);
  \path[name path=lineFA'] (F) -- (A');
  \path[name intersections={of=lineCD and lineFA',name=sectionA}];
  \coordinate (A) at (sectionA-1);
  \path[name path=lineCE'] (C) -- (E');
  \path[name intersections={of=lineFD and lineCE',name=sectionE}];
  \coordinate (E) at (sectionE-1);
  \path[draw, name path=lineFA] (F) to[bend right=30] (A);
  \path[draw, name path=lineCE] (C) to[bend left=30] (E);
  \path[name intersections={of=lineFA and lineCE,name=sectionB}];
  \coordinate (B) at (sectionB-1);
  \draw (A) +(90:0.2) node{$a$};
  \draw (B) +(180:0.2) node{$b$};
  \draw (C) +(180:0.2) node{$c$};
  \draw (D) +(20:0.2) node{$d$};
  \draw (E) +(-90:0.2) node{$e$};
  \draw (F) +(180:0.2) node{$f$};
 \end{tikzpicture}
\end{document}