no. 3
Lax Kan extensions for double categories (on weak double categories, part IV)
Cahiers de Topologie et Géométrie Différentielle Catégoriques, Tome 48 (2007) no. 3, pp. 163-199. 
@article{CTGDC_2007__48_3_163_0,
     author = {Grandis, Mario and Pare, Robert},
     title = {Lax Kan extensions for double categories (on weak double categories, part IV)},
     journal = {Cahiers de Topologie et G\'eom\'etrie Diff\'erentielle Cat\'egoriques},
     pages = {163--199},
     publisher = {Dunod \'editeur, publi\'e avec le concours du CNRS},
     volume = {48},
     number = {3},
     year = {2007},
     zbl = {1131.18004},
     mrnumber = {2351267},
     language = {en},
     url = {archive.numdam.org/item/CTGDC_2007__48_3_163_0/}
}
Grandis, Mario; Pare, Robert. Lax Kan extensions for double categories (on weak double categories, part IV). Cahiers de Topologie et Géométrie Différentielle Catégoriques, Tome 48 (2007) no. 3, pp. 163-199. http://archive.numdam.org/item/CTGDC_2007__48_3_163_0/

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