@article{RSMUP_1988__79__153_0,
     author = {Dugas, Manfred},
     title = {On some subgroups of infinite rank {Butler} groups},
     journal = {Rendiconti del Seminario Matematico della Universit\`a di Padova},
     pages = {153--161},
     publisher = {Seminario Matematico of the University of Padua},
     volume = {79},
     year = {1988},
     mrnumber = {964027},
     zbl = {0667.20043},
     language = {en},
     url = {http://archive.numdam.org/item/RSMUP_1988__79__153_0/}
}