Cita APA

(1990). Revised water usage & classification, water quality criteria amending section #68 & 69, chapter III of the NPCC rules and regulations. s.n.

Citación estilo Chicago

Revised Water Usage & Classification, Water Quality Criteria Amending Section #68 & 69, Chapter III of the NPCC Rules and Regulations. [s.l: s.n, 1990.

Cita MLA

Revised Water Usage & Classification, Water Quality Criteria Amending Section #68 & 69, Chapter III of the NPCC Rules and Regulations. s.n, 1990.