2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/111471An example is given which shows that, in general, conditioned Galton-Watson trees cannot be obtained by adding vertices one by one, as has been shown in a special case by Luczak and Winkler.5 pages, 2 figuresProbabilityCombinatorics60C05; 05C05text