KATCHALSKI, Meir. A conjecture of Grünbaum on common transversals. Mathematica Scandinavica, Berkeley, CA, United States, v. 59, p. 192–198, 1986. DOI: 10.7146/math.scand.a-12161. Disponível em: https://journals.msp.org/mscand/article/view/1515. Acesso em: 25 jul. 2026.