• 8th International Conference "Resource Reproducing, Low-wasted and Environmentally Protecting Technologies of Development of the Earth Interior" September 14-18, Tallinn 2009, EstoniaSabanov, SergeiOil shale2009 / p. 543 https://go.gale.com/ps/i.do?id=GALE%7CA216339232&sid=googleScholar&v=2.1&it=r&linkaccess=abs&issn=0208189X&p=AONE&sw=w&userGroupName=anon%7E8276c49e&aty=open-web-entry