00500 2200169 4500001002100000008004100021035002000062245004800082100002100130260004200151300005100193084001600244520002200260082001200282650001600294990002000310INLIS000000000008787 Ind  a0010-1118008787 aError detecting decimal codescVERHOEFF, J. aJacobus Verhoeff aAmsterdambMathematisch Centrumc1969 a118 p. : ill. ; 25 cm.c118 p. : ill. ; 25 cm. a511.135VERe aBibl.: p. 112-118 a511.135 aMATHEMATICS a134/71-mfn10566