1. Logaritmy Creator: BALADA, Fr. Format: electronic Type: model:article and TEXT Language: Czech Rights: http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
2. Věta Pythagorova Creator: BALADA, Fr. Format: electronic Type: model:article and TEXT Language: Czech Rights: http://creativecommons.org/publicdomain/mark/1.0/ and policy:public