Helcké, G. (1981). The energy saving guide: Tables for assessing the profitability of energy saving measures with explanatory notes and worked examples. Pergamon Press.
Chicago-Zitierstil (17. Ausg.)Helcké, George. The Energy Saving Guide: Tables for Assessing the Profitability of Energy Saving Measures with Explanatory Notes and Worked Examples. Oxford: Pergamon Press, 1981.
MLA-Zitierstil (9. Ausg.)Helcké, George. The Energy Saving Guide: Tables for Assessing the Profitability of Energy Saving Measures with Explanatory Notes and Worked Examples. Pergamon Press, 1981.
Achtung: Diese Zitate sind unter Umständen nicht zu 100% korrekt.