A few Burke Photo Questions and Burke Show'em thread.

[drc]

Yours are originals, first run as you said. There are later reprints, but they have different stamping. There will be some other examples, but not a lot. The serial number is the number identifying the negative used. The original negatives were probably filed in envelopes with the identical numbers on the outside. Many professional photos have similar i.d. numbers, sometimes written on back.