@article{CMH_1991__66_4_140234,
     author = {Ma Li},
     title = {Harmonic map heat flow with free boundary.},
     journal = {Commentarii mathematici Helvetici},
     pages = {279--301},
     publisher = {mathdoc},
     volume = {66},
     number = {4},
     year = {1991},
     zbl = {0727.53044},
     url = {http://geodesic.mathdoc.fr/item/CMH_1991__66_4_140234/}
}