@article{JAC_1997__6_3_a1,
     author = {Schmidt, Bernhard},
     title = {On $(p\sp a,p\sp b,p\sp a,p\sp{a-b})$-relative difference sets},
     journal = {Journal of Algebraic Combinatorics},
     pages = {279--297},
     publisher = {mathdoc},
     volume = {6},
     number = {3},
     year = {1997},
     language = {en},
     url = {http://geodesic.mathdoc.fr/item/JAC_1997__6_3_a1/}
}