Is there an index of Downbeat magazine articles?

I have a lot of old DOWNBEAT magazines beginning in the early 1960's -with a few back to 1945-and I enjoy brousing them but often I see an interesting article and later I can't locate it again. The only sort of index I know about the is the 'New Grove Dictionary of Jazz' which has DOWNBEAT references at the end of various musicians sections. This is not much of a help but can enable you to locate some of the material.

It would be tremendous to have a complete DOWNBEAT index on line to consult!