Department of Education භෞතික විද්යාව 12 වන ශ්රේණීය - Department of Education Publisher Mahragam 2020 - 92p 1 - 2024-03-04 ISBN: 978-955-654-884-6 Nat. Bib. No.: 009374 Nat. Bib. Agency Control No.: SCI Universal Decimal Class. No.: 540