The nature of some supposed algal coals.

[1] BERTRAND CE, 1892, PILA BIBRACTERSIS BO

[2] POTONIE H, 1907, ENTSTEHUNG STEINKOHL

[3] RENAULT B, 1892, COMMUNICATION FAITE

[4] *SOC HIST NAT AUT, 1894, B SOC HIST NAT AUT

[5] *SOC IND MIN, 1900, B SOC IND MIN, V14

[6] *SOC IND MIN, 1899, B SOC IND MIN, V13

[7] *U LILL, 1898, TRAV MEM U LILL, V21

[8] ENTSTEHUNG STEINKOHL, P20

[9] 1907, REV MOIS, V3, P323

[1] BERTRAND CE, 1892, PILA BIBRACTERSIS BO

[2] POTONIE H, 1907, ENTSTEHUNG STEINKOHL

[3] RENAULT B, 1892, COMMUNICATION FAITE

[4] *SOC HIST NAT AUT, 1894, B SOC HIST NAT AUT

[5] *SOC IND MIN, 1900, B SOC IND MIN, V14

[6] *SOC IND MIN, 1899, B SOC IND MIN, V13

[7] *U LILL, 1898, TRAV MEM U LILL, V21

[8] ENTSTEHUNG STEINKOHL, P20

[9] 1907, REV MOIS, V3, P323