Gaya APA

The handbook for waterworks operator certification : vol. 1. Fundamental level -- vol. 2. Intermediate level -- vol. 3. Advanced level / Frank R. Spellman, Joanne E. Drinan. (2001). : Lancaster, Technomic Publishing.

Gaya MLA

The handbook for waterworks operator certification : vol. 1. Fundamental level -- vol. 2. Intermediate level -- vol. 3. Advanced level / Frank R. Spellman, Joanne E. Drinan. . : Lancaster, Technomic Publishing, 2001. Text.