If one needs to use tools from classical invariant theory or elimination theory then some books that come to mind are: - Grace and Young <a href="http://books.google.com/books?id=PhoPAAAAIAAJ&printsec=frontcover#v=onepage&q&f=false">"The Algebra of Invariants"</a> - Elliott <a href="http://books.google.com/books?id=Az5tAAAAMAAJ&printsec=frontcover#v=onepage&q&f=false">"An Introduction to The Algebra of Quantics"</a> - Salmon <a href="http://books.google.com/books?id=NJ0KAAAAYAAJ&printsec=frontcover#v=onepage&q&f=false">"Lessons Introductory to The Modern Higher Algebra"</a> - Faa di Bruno <a href="http://books.google.com/books?id=gDIAAAAAQAAJ&printsec=frontcover#v=onepage&q&f=false">"Théorie Des Formes Binaires"</a> - Faa di Bruno <a href="http://books.google.com/books?id=QflACY8TFnQC&printsec=frontcover#v=onepage&q&f=false">"Théorie Générale de l'Elimination"</a> and there are quite a few more.