@article{10_4064_ap_24_2_113_119,
     author = {Jan Bochenek},
     title = {On some properties of eigenvalues and eigenfunctions of certain differential equations of the fourth order},
     journal = {Annales Polonici Mathematici},
     pages = {113--119},
     publisher = {mathdoc},
     volume = {24},
     number = {2},
     year = {1970},
     doi = {10.4064/ap-24-2-113-119},
     language = {en},
     url = {http://geodesic.mathdoc.fr/articles/10.4064/ap-24-2-113-119/}
}