@article{DAN_1968_183_3_a2,
     author = {B. Efimov},
     title = {Extremally disconnected bicompacta whose $\pi$-weight is the continuum},
     journal = {Doklady Akademii Nauk},
     pages = {511--514},
     year = {1968},
     volume = {183},
     number = {3},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/DAN_1968_183_3_a2/}
}