The Marshall-Olkin Flexible Weibull Extension Distribution
  This paper introduces a new generalization of the flexible Weibull distribution with three parameters this model called the Marshall-Olkin flexible Weibull extension (MO-FWE) distribution which exhibits bathtub-shaped hazard rate. We studied it's statistical properties include, quantile function skewness and kurtosis, the mode, rth moments and moment generating function and order statistics. We used the method of maximum likelihood for estimating the model parameters and the observed Fisher's information matrix is derived. We illustrate the usefulness of the proposed model by applications to real data. 
Abdelfattah Mustafa, B.S.El-Desouky and Shamsan AL-Garash
math.ST stat.TH