@article{01018686,
title = {Harmonic maps of Lorentz surfaces, quadratic differentials and paraholomorphicity.},
journal = {Beitr\"age zur Algebra und Geometrie},
volume = {38},
year = {1997},
pages = {19-32},
zbl = {0879.58015},
language = {en},
url = {http://dml.mathdoc.fr/item/01018686}
}
Erdem, Sadettin. Harmonic maps of Lorentz surfaces, quadratic differentials and paraholomorphicity.. Beiträge zur Algebra und Geometrie, Tome 38 (1997) pp. 19-32. http://gdmltest.u-ga.fr/item/01018686/