Here is what I found for the 24 cards in Series #15 so far. It looks like the first print run has no letter. I've only found those from Italy. Is there a first print run from Japan? In addition, I am finding print run "A" and print run "B". So I'm working on getting all three versions for Series #15.
I have every card from the first print run and the 'B' print run. I am only missing one card (#22) from the 'A' print run.
Here are the back variations I've seen. I have yet to check for variations on the front of the cards.
15-01 The European Cup Winner - all three have different results
15-02 Roy Schuiten - 'A' and 'B' have updated results and text
15-06 Althea Gibson - 'A' and 'B' have reformatted text
15-18 Tornado (Yachting) - 'A' and 'B' have different captions
15-22 Heinz Gunthardt - 'B' has more awards listed
