@article{JLT_2004_14_2_JLT_2004_14_2_a3,
     author = {R. Ghanam and G. Thompson and E. J. Miller},
     title = {Variationality of {Four-Dimensional} {Lie} {Group} {Connections}},
     journal = {Journal of Lie theory},
     pages = {395--425},
     publisher = {mathdoc},
     volume = {14},
     number = {2},
     year = {2004},
     url = {http://geodesic.mathdoc.fr/item/JLT_2004_14_2_JLT_2004_14_2_a3/}
}