@article{JRAM_1974__267_151434,
     author = {Philip Pratt},
     title = {Operations in {Lapan's} class {B*.}},
     journal = {Journal f\"ur die reine und angewandte Mathematik},
     pages = {67--73},
     publisher = {mathdoc},
     volume = {267},
     year = {1974},
     zbl = {0284.30021},
     url = {http://geodesic.mathdoc.fr/item/JRAM_1974__267_151434/}
}