@article{10_4064_ap_24_1_71_76,
     author = {M. Lorens},
     title = {Scalar differential concomitants of the second order of the metrical tensor in three-dimensional {Riemann} spaces},
     journal = {Annales Polonici Mathematici},
     pages = {71--76},
     publisher = {mathdoc},
     volume = {24},
     number = {1},
     year = {1970},
     doi = {10.4064/ap-24-1-71-76},
     language = {en},
     url = {http://geodesic.mathdoc.fr/articles/10.4064/ap-24-1-71-76/}
}