“…Energy . (Bowen et al, 1999; Buchholz et al, 2009; Buchholz and Silva, 2010; Christensen and Valqui Vidal, 1990; Fichani and Labys, 2006; Gabreyohannes, 2010; Gilau and Small, 2008; Hosier and O'Keefe, 1983; Jingura and Matengaifa, 2009; Kaboudan, 1989; Kagiannas et al, 2003; Luhanga et al, 1993; Murck et al, 1985; Mwakabuta and Kyaruzi, 2003, 2005; Nderitu et al, 1998; Parshall et al, 2009; Ramanathan, 2002; van den Broek and Lemmens, 1997; Wiskerke et al, 2010)…”