Salutation exhibit short prints
 

I know it's generally impossible to date a specific salutation exhibit to a certain year since the same cards were issued over many years, but in the case of short prints that's not so true.

I've read all the articles on line and threads here but no one seems to want to step up with commitments to answers. There are several experts on these cards here so I thought I'd try again.

Is it safe to assume that most of the cards below were issued in 1939? I know only 16 cards were released that year and since several of them either saw their career end then or greatly diminished for a year later.

If the 16 cards from 1939 could be confirmed that might answer some questions. I'm guessing each one of these were in 1939, but how many other years did these short prints appear?

Lou Gehrig (last season 1939)
Earl Averill (1941)
Gabby Hartnett (1941)
Chuck Klein (last significant season 1941)
Hugh Mulcahy (1942)
Johnny Rizzo (1942)
Mike Kreevich (1945)