Gaya APA

Puzinauskas, , V. (1978). Differences Between Petroleum Asphalt, Coal-Tar Pitch and Road Tar . Maryland: The Asphalt Institute.

Gaya MLA

Puzinauskas, , V.P.. "Differences Between Petroleum Asphalt, Coal-Tar Pitch and Road Tar". Maryland: The Asphalt Institute, 1978. Text.