00303nam a2200121Ia 45000030006000000080041000060400015000471000042000622450039001042600009001435460012001520050017001640STCL150530s9999    xx            000 0 und d  aSTCLcSTCL  aNational Council of Science Education  aJournal of Physics Education March  c1973  aEnglish20220125165829.0