“…The case of singular, but integral curves, mainly nodal curves, is discussed in work of U. N. Bhosle [Bh2,Bh3] and references therein. The case of reducible curves appeared in [Bh1,BF1,BF2] and we will discuss it in subsection 4.3. Further classical results of Brill-Noether theory appear in [LN2,LN3,LN4,LNP,LNS].…”