@article{MV_1965_17_3_a0,
     author = {M. D. Leko},
     title = {On the concept of energy in the classical mechanics and relativity},
     journal = {Matemati\v{c}ki vesnik},
     pages = {173 },
     year = {1965},
     volume = {17},
     number = {3},
     url = {http://geodesic.mathdoc.fr/item/MV_1965_17_3_a0/}
}