The principles of petrology : an introduction to the science of rocks /

Eitemau Tebyg

• The principles of petrology : an introduction to the science of rocks /
  gan: Tyrrell, G. W. (George Walter), 1883-
  Cyhoeddwyd: (1929)
• The principles of petrology : an introduction to the science of rocks /
  gan: Tyrrell, G. W. (George Walter), 1883-
  Cyhoeddwyd: (1949)
• Petrology for students : an introduction to the study of rocks under the microscope.
  gan: Harker, Alfred, 1859-1939
  Cyhoeddwyd: (1902)
• Petrology for students; an introduction to the study of rocks under the microscope.
  gan: Harker, Alfred, 1859-1939
  Cyhoeddwyd: (1919)
• Petrology for students : an introduction to the study of rocks under the microscope.
  gan: Harker, Alfred, 1859-1939
  Cyhoeddwyd: (1954)