Danapala,A.H ප්රායෝගික භූගෝලවිද්යාව - Sarasavi Publishers Nugegoda 2018 - 239p 1 - 2023-10-25 ISBN: 978-955-31-1150-0 Nat. Bib. No.: 0007544 Nat. Bib. Agency Control No.: DAN Universal Decimal Class. No.: 900