A geological investigation on the limestone hills of G.Keroh, G. Merawan, G. Karang Besar and G. Karang Kecil, Simpang Pulai Area, Kinta District, Perak - Ong, Wee Seck; Malaysia. Jabatan Penyiasatan Kajibumi (Ipoh : Ibu Pejabat Penyiastan Kajibumi, 1977)
Keywords: Limestone -- Perak; Mountains -- Perak; Investigative reporting -- Perak