1. Taschenbuch für Heizung und Klimatechnik;Recknagel,1981
2. Estimation of daily degree-hours;Guttman;J Appl Meteorol,1992
3. Taschenbuch für Heizung und Klimatechnik;Recknagel,1993
4. Heating degree-day variations in Turkey;Kadıoğlu;Proc of the Fifth International Symposium on Environmental Issues and Waste Management in Energy and Mineral Production-SWEMP’98, Ankara-Turkey. 18–20 May,1998
5. Degree-day formulations and application in Turkey;Kadıoğlu;J Appl Meteorol,1999