https://www.proz.com/personal-glossaries/entry/32633429-analysis-of-two-independent-proportions-tests-%D0%B0%D0%BD%D0%B0%D0%BB%D0%B8%D0%B7-%D0%B4%D0%B2%D1%83%D1%85-%D0%BF%D1%80%D0%BE%D0%BF%D0%BE%D1%80%D1%86%D0%B8%D0%BE%D0%BD%D0%B0%D0%BB%D1%8C%D0%BD%D1%8B%D1%85-%D0%B7%D0%B0%D0%B2%D0%B8%D1%81%D0%B8%D0%BC%D0%BE%D1%81%D1%82%D0%B5%D0%B9-%D0%B2-%D0%BD%D0%B5%D1%81%D0%B2%D1%8F%D0%B7%D0%B0%D0%BD%D0%BD%D1%8B%D1%85-%D0%B2%D1%8B%D0%B1%D0%BE%D1%80%D0%BA%D0%B0%D1%85