\magnification=1200
\hsize=4in
\nopagenumbers
\noindent
{\bf Andr\'{e} Bouchet}
\medskip
\noindent
{\bf Multimatroids II. Orthogonality, minors and connectivity}
\vskip.5cm


A multimatroid is a combinatorial structure that encompasses matroids,
  delta-matroids and isotropic systems. This structure has been
  introduced to unify a theorem of Edmonds on the coverings of a matroid
  by independent sets and a theorem of Jackson on the existence of
  pairwise compatible Euler tours in a 4-regular graph. Here we
  investigate some basic concepts and properties related with
  multimatroids: matroid orthogonality, minor operations and
  connectivity.

\bye