Author/Authors :
E.J. Cockayne، نويسنده , , S.M. Hedetniemi، نويسنده , , S.T. Hedetniemi، نويسنده , , C.M. Mynhardt، نويسنده ,
Abstract :
For any tree T, it is proved that θ(T), the smallest cardinality of a perfect neighbourhood set, is bounded above by ir(T), the smallest cardinality of a maximal irredundant set.
