Interfax: Russia & CIS oil & gas weekly. Interfax-America.
Chicago-čujuhus (17. p.)Interfax: Russia & CIS Oil & Gas Weekly. Aurora, Colorado: Interfax-America.
MLA-čujuhus (9. p.)Interfax: Russia & CIS Oil & Gas Weekly. Interfax-America.
Muitte dárkkistit čujuhemiid riektatvuođa, ovdal go geavahat daid iežat deavsttas.