2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/46710A few remarks concerning theoretical suggestions and experimental tests of CPT during 1980's - 1990's. Is it worth to search for the particle-antiparticle mass differences in sectors other than $K^0\bar{K}^0$?Latex, 5 pages,Talk at the Workshop on $K$-physics, ORSAY, France, 30 May - 4 June, 1996High Energy Physics - Phenomenologytext