| • coal bed | |
| कोयला: carbon coal collier brown coal lignite fuel | |
| संस्तर: bed calcic horizon diagnostic surface horizons | |
कोयला संस्तर अंग्रेज़ी में
[ koyala samstar ]
| • coal bed | |
| कोयला: carbon coal collier brown coal lignite fuel | |
| संस्तर: bed calcic horizon diagnostic surface horizons | |
