Matti Nykänen, Esko Ukkonen. The Exact Path Length Problem. J. Algorithms, 42(1):41-53, 2002. [doi]
@article{NykanenU02, title = {The Exact Path Length Problem}, author = {Matti Nykänen and Esko Ukkonen}, year = {2002}, doi = {10.1006/jagm.2001.1201}, url = {http://dx.doi.org/10.1006/jagm.2001.1201}, researchr = {https://researchr.org/publication/NykanenU02}, cites = {0}, citedby = {0}, journal = {J. Algorithms}, volume = {42}, number = {1}, pages = {41-53}, }