Alex Unya Ambun <br/><br/>
Report on quarry site investigation at Sungei Bua Batang Oya  GSKL 017/227 
Alex Unya Ambun, Gasah Lingkai 
 -  1980 
 - 1 v.(various pagings)  ill.  30 cm 
<br/><br/> Substantial reserve of good quality sandstone is believed to occur within the ridge 
<br/><br/><label>Subjects--Topical Terms: </label><br/>Quarries and quarrying--Batang Oya--Sarawak