@article{CMH_1987__62_140079,
     author = {Andrzej Derdzinski and Ch. B. Croke},
     title = {A lower bound for ... on manifolds with boundary.},
     journal = {Commentarii mathematici Helvetici},
     pages = {106--121},
     year = {1987},
     volume = {62},
     zbl = {0617.53047},
     url = {http://geodesic.mathdoc.fr/item/CMH_1987__62_140079/}
}