My mistake -
After looking closer at both documents I noticed that these are 2 different reports:
Document NM_APR_1_1951.pdf is dated: April 1 1951 and
Document NM_MAR_12_1951.pdf is dated: March 12 1951
But both having exactly the same 2nd. pdf page released by L. Elterman and approved by P.H.Wyckoff (November 27 1951)
Newsflash:
The Project Twinkle final report was released by L. Elterman and I believe this was attached to the case file but went missing while scanning these
documents:
Project 1947 (Twinkle Final Report)

Early in 1950 the Geophysics Research Division received a directive to investigate peculiar light phenomena that had been observed in the skies of
the southwestern United States. Project Twinkle was established to check into these phenomena and their explanation....
[edit on 27-1-2008 by frozen_snowman]