Pengantar metode statistik - Anto Dajan (LP3ES, 1995)
tr, Jil.1=c.1-12; Jil.2=c.1-10 / ir,jil.1,c.13 ;jil.2,c.11/ tr, jil.1=c.14-15; jil.2=c.12-17/nr, jil.1=.33-.35