00301nam a2200121Ia 45000030006000000080041000060400015000471000042000622450037001042600009001415460012001500050017001620STCL150530s9999    xx            000 0 und d  aSTCLcSTCL  aNational Council of Science Education  aJournal of Physics Education May  c1979  aEnglish20220125165829.0