S.L.Loni ද්රවස්ටිති විද්යා - Educational Department Of Education Colombo 1958 - 204p 1 - 2023-12-19 ISBN: 978-955-25-0485-3 Nat. Bib. No.: 0008382 Nat. Bib. Agency Control No.: LON Subjects--Topical Terms: Mathematics(AL) Universal Decimal Class. No.: 530