@article{SM_2021_212_3_a6,
     author = {S. Mori and Yu. G. Prokhorov},
     title = {General elephants for threefold extremal contractions with one-dimensional fibres: exceptional case},
     journal = {Sbornik. Mathematics},
     pages = {351--373},
     publisher = {mathdoc},
     volume = {212},
     number = {3},
     year = {2021},
     language = {en},
     url = {http://geodesic.mathdoc.fr/item/SM_2021_212_3_a6/}
}