Gaya APA

(API), A, P, I. (1990). Specification for low pressure fiberglass line pipe. API Specification 15LR (Spec 15LR). (1990). : Washington DC : American Petroleum Inst.,.

Gaya MLA

(API), American, Petrol., Inst.. "Specification for low pressure fiberglass line pipe. API Specification 15LR (Spec 15LR).". 1990 : Washington DC : American Petroleum Inst.,, 1990. Text.