@article{MS2_1984__54_166895,
     author = {Arne Jensen},
     title = {On {Lavine's} formula for time-delay.},
     journal = {Mathematica Scandinavica},
     pages = {253--261},
     year = {1984},
     volume = {54},
     zbl = {0529.46006},
     url = {http://geodesic.mathdoc.fr/item/MS2_1984__54_166895/}
}