1. An approbation on the sefer ‘V’yelaket Yoseph’ by R. Yoseph Mandelcorn. This approbation is completely different than the one printed in his book (and repeated in ‘Igroth HaGriz Halevi p. 373). This letter is dated 12 Iyar 709 whereas the printed version is dated 12 Elul 709. It remains unclear why a second approbation was written.
2. A letter of recommendation written in 1941! To the Va’ad Agudath Yisrael to assist Abba Zions (a resident of Brisk and a student of his – later studied in Mir).
Both letters are autographs – written and signed by the Brisker Rav!