Developed as a labor of love for Marvel trading cards (and some others) this checklist site is for informational purposes only. I stopped collecting some time back so these checklists are by no means complete to the present day. An excellent reference is Comic Cards and Their Prices by Stuart Wells III, Wallace-Homestead Book Co. publishers. However, it was published in 1994, and so doesn't have the most recent sets (and I haven't seen any later editions).