@article{MET_1986__33_176079,
     author = {L.J. Willson and J.L. Folks and J.H. Young},
     title = {Complete {Sufficiency} and {Maximum} {Likelihood} {Estimation} for the {Two-Parameter} {Negative} {Binomial} {Distribution.}},
     journal = {Metrika},
     pages = {349--362},
     publisher = {mathdoc},
     volume = {33},
     year = {1986},
     zbl = {0602.62021},
     url = {http://geodesic.mathdoc.fr/item/MET_1986__33_176079/}
}