M. Abouammoh, A. et N. Ahmed, A., The new better than used failure rate class of life distribution, Advances in applied probability , 20(1), 1988, pp. 237-240
A new concept of ageing distribution, namely new better than used in failure rate (NBUFR), is introduced. Different properties of the NBUFR class and its dual class are presented. Its relations to other classes of life distributions are investigated. Finally, NBUFR survival under shock models is discussed.