“Justice League Europe / International” #6 and #10 have 2nd printings (this was from the massive number of DC multipacks from the late 1980s through the early 1990s).
The covers appear identical to the 1st printings. Both of the 2nd printings use the Lynx back cover:
The back cover is the easiest way to spot the reprints. The Core already has the back cover for the 1st printing of #6 (the TSR cover).
The back cove to the 1st printing of #10 is:
