@article{JDM_1972__74_146609,
     author = {H. Rund and D. Lovelock},
     title = {Variational {Principles} in the {General} {Theory} of {Relativity.}},
     journal = {Jahresbericht der Deutschen Mathematiker-Vereinigung},
     pages = {1--65},
     publisher = {mathdoc},
     volume = {74},
     year = {1972},
     zbl = {0246.49038},
     url = {http://geodesic.mathdoc.fr/item/JDM_1972__74_146609/}
}