@article{10_1090_S0894_0347_05_00511_4,
     author = {Cheeger, Jeff and Tian, Gang},
     title = {Curvature and injectivity radius estimates for {Einstein} 4-manifolds},
     journal = {Journal of the American Mathematical Society},
     pages = {487--525},
     publisher = {mathdoc},
     volume = {19},
     number = {2},
     year = {2006},
     doi = {10.1090/S0894-0347-05-00511-4},
     url = {http://geodesic.mathdoc.fr/articles/10.1090/S0894-0347-05-00511-4/}
}