Circular The Geological Survey. Department Mines, Mining & Geology. State Div. Conserva.
Cita Chicago Style (17a ed.)Circular The Geological Survey. USA: Department Mines, Mining & Geology. State Div. Conserva.
Cita MLA (8a ed.)Circular The Geological Survey. Department Mines, Mining & Geology. State Div. Conserva.
Precaución: Estas citas no son 100% exactas.