A class of multivariate distributions which is an extension of the class of univariate distributions with increasing failure rate averages is introduced. Properties of this class are studied and examples of distributions which are members of this class are given.
Henry W. Block. Thomas H. Savits. "Multivariate Increasing Failure Rate Average Distributions." Ann. Probab. 8 (4) 793 - 801, August, 1980. https://doi.org/10.1214/aop/1176994666