Merdeka, 6 April 1951: Batik Workers' Union conference
Merdeka, 6 Apr 1951, p. 2: Serikat Buruh Batik conference on fusion with the textile union; Gerwis listed among the guests and those who gave greetings, with SOBSI and MPs Werdojo and Pardede.
Merdeka, 25 April 1951: May Day 1951 preparations
Merdeka, 25 April 1951 (hlm. 2): plans for May Day 1951 by a central committee (SOBSI, KABM) assisted by the Peace Defence Committee, Lekra, Pemuda Rakyat, Sakti and Gerwis, framed as defence of world peace.
Commemoration of 1 May 1951 in Surakarta (Bentara)
Full-page notice in the Surakarta magazine Bentara listing the organising committee of the 1 May 1951 Labour Day commemoration, a left united front dominated by SOBSI unions and including Gerwis.