In M/MC 31/2, he is clearly identified by name on 5:5. He's also most likely in issue M/MC 30, but since he's only called lieutenant and there seems to be many of them, we cannot be 100% sure. If others sources confirm it, it would be placed right before issue 31.
FOLMA, LT.
...
HTC 3/2
M/MC 31/2 <-- ADD
SUBC 5
HTC 7/4
Missing issues for Folma
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