Recently landed on auction lots for this coin series. Without much study, I sought to identify any varieties such as DDOs, DDRs and then I realized this series is a different game. Still, the pictures below are:
(a) to learn if in fact the first is a DDR
and the second, a die clash
(b) if yes, is there a premium for these varieties ?
Should there be a reference book on this series or era of coin minting, please educate, I arrived at this book after a Google Search..