WWII over Czechoslovakia?

I remember reading about a series of books written in the 30s which has the premise of WWII happening when Germany invades Czechoslovakia? Does anyone remember the titles?
No, these books were written in the 1930s, sort of Tom Clancy style, but after the outbreak of WWII I guess they become Alternate History, sort of similar to Red Storm Rising or most of the Jack Ryan series.