Essential arithmetic
Johnston, C. L.
Essential arithmetic /C.L. Johnston ; Alden T. Willis ; Jeanne Lazaris - 7th ed. - Boston : PWS Pub., 1995. - xvii, 792p. : ill. ; 28cm
Essential arithmetic /C.L. Johnston ; Alden T. Willis ; Jeanne Lazaris - 7th ed. - Boston : PWS Pub., 1995. - xvii, 792p. : ill. ; 28cm