@article{10_4064_am_21_2_283_287,
     author = {R. H. Warren},
     title = {Polynomially solvable traveling salesman problems},
     journal = {Applicationes Mathematicae},
     pages = {283--287},
     publisher = {mathdoc},
     volume = {21},
     number = {2},
     year = {1991},
     doi = {10.4064/am-21-2-283-287},
     zbl = {0741.90089},
     language = {en},
     url = {http://geodesic.mathdoc.fr/articles/10.4064/am-21-2-283-287/}
}