…depth (Schneider, 2005a, 2008, 2010c), by minimizing the number of sums arising within the summand (Schneider, 2004, 2015), or minimizing the degree of the sums and products arising in the summands and multiplicands (Abramov, 1975; Paule, 1995; Schneider, 2005b, 2007a; Abramov and Petkovšek, 2010).