TY - JOUR T1 - The role of the protractor in understanding the universe A1 - Křížek, Michal JA - Obzory matematiky, fyziky a informatiky Y1 - 2008 VL - 37 IS - 1 SP - 36 EP - 47 SN - 1335-4981 N2 - We present several examples to show how such an ordinary and simple instrument as the usual protractor helped to create the modern view of the universe. ER -