Bill, D. (1991). Practical home energy savings. The Institute.
Citazione stile Chigago Style (17a edizione)Bill, David. Practical Home Energy Savings. Snowmass, CO (1739 Snowmass Creek Rd., Snowmass 81654-9199): The Institute, 1991.
Citatione MLA (8a ed.)Bill, David. Practical Home Energy Savings. The Institute, 1991.
Attenzione: Queste citazioni potrebbero non essere precise al 100%.