American Society For Testing Materials. (1974). Standard Specification For Concrete Aggregates Astm C33-74a.
Cita Chicago Style (17a ed.)American Society For Testing Materials. Standard Specification For Concrete Aggregates Astm C33-74a. 1974.
Cita MLA (9a ed.)American Society For Testing Materials. Standard Specification For Concrete Aggregates Astm C33-74a. 1974.
Precaución: Estas citas no son 100% exactas.