参考文献
Thomas J. Jech, Set Theory: The Third Millennium Edition, revised and expanded, Springer, 2011
A. Hajnal, The chromatic number of the product of two ℵ1-chromatic graphs can be countable, Combinatorica 5 (), 1985, pp. 137-139
A. Rinot, Hedetniemi’s conjecture for uncountable graphs, J. Eur. Math. Soc. 19 (1), 2017, pp. 285-291