Herath, J.W. Mineral based industries of Sri Lanka - NARESA Colombo 1986 - 87 lk - Sri Lanka Economic minerals Ferrous group Ferro Alloy Group Non-ferrous mineral group Non-metallic mineral group Mineral Policy - Science Education Series No.15 . http://thakshana.nsf.ac.lk/slstic/NA-108/NA_108_i.pdf = Herath, J.W. Standard No.: M Standard Tech. Report. No.: LCCN: B Nat. Bib. No.: NA-108 Nat. Bib. Agency Control No.: NA-108 Subjects--Topical Terms: EducationMineralogy Universal Decimal Class. No.: 37