Back in the early 90's, I was just getting started collecting hockey cards, but I didn't know much about older players at all. I went to the local library and found some excellent books on hockey players from the early 1900's through the 60's. One book was an oversized hardback book. On the inside of the cover, there were C55's pictured, along with possibly some C56's and others. I didn't know much about pre-war cards at all, but I loved looking at the pictures.
I don't remember the name of the book, but hopefully someone has seen it or even has a copy. If you are familiar with this book, please let me know the title and author so that I can find a copy.