@article{10_4064_fm80_9_2016,
     author = {Hans U. Boden and Robin Gaudreau and Eric Harper and Andrew J. Nicas and Lindsay White},
     title = {Virtual knot groups and almost classical knots},
     journal = {Fundamenta Mathematicae},
     pages = {101--142},
     publisher = {mathdoc},
     volume = {238},
     number = {2},
     year = {2017},
     doi = {10.4064/fm80-9-2016},
     language = {en},
     url = {http://geodesic.mathdoc.fr/articles/10.4064/fm80-9-2016/}
}