1. Two-fold theorem on Fréchetness of products Creator: Dolecki, Szymon and Nogura, Tsugunori Format: bez média and svazek Type: model:article and TEXT Subject: $\alpha_3$, $\alpha_4$, $\beta_3$, $\beta_4$, 4$ spaces, $\Phi$-space, product space, sequential space, sequentially subtransverse, strongly Fréchet, and transverse Language: English Description: A refined common generalization of known theorems (Arhangel’skii, Michael, Popov and Rančin) on the Fréchetness of products is proved. A new characterization, in terms of products, of strongly Fréchet topologies is provided. Rights: http://creativecommons.org/publicdomain/mark/1.0/ and policy:public