@article{SLC_1991_26_a8,
     author = {Josef Wolfgang Degen},
     title = {Some {Contributions} to the {Model} {Theory} of {Mono-Unaries}},
     journal = {S\'eminaire lotharingien de combinatoire},
     publisher = {mathdoc},
     volume = {26},
     year = {1991},
     url = {http://geodesic.mathdoc.fr/item/SLC_1991_26_a8/}
}