On the geometry of the
moduli spaces of semi-stable sheaves supported on plane quartics . Geometriae Dedicata 152 (2011), 17-49.
We decompose each moduli space of semi-stable sheaves on the complex projective
plane with support of dimension one and degree four into locally closed
subvarieties, each subvariety being the good or geometric quotient of a set of
morphisms of locally free sheaves modulo a reductive or a non-reductive group.
We find locally free resolutions of length one of all these sheaves and