The Annals of Statistics, Vol. 10, No. 2 (Jun., 1982), pp. 479-484 (6 pages) Arbitrary nonparametric mixtures of exponential and Weibull (fixed shape) distributions are considered as possible models ...

The 95% profile likelihood confidence interval for the scale parameter is (0.6959, 0.9762), which does not contain 1. The hypothesis of an exponential distribution for the data is, therefore, rejected ...

Albert W. Marshall, Ingram Olkin, A Generalized Bivariate Exponential Distribution, Journal of Applied Probability, Vol. 4, No. 2 (Aug., 1967), pp. 291-302 ...