@article{JGG_2008_12_2_JGG_2008_12_2_a2,
     author = {G. Nawratil },
     title = {On the {Degenerated} {Cases} of {Architecturally} {Singular} {Planar} {Parallel} {Manipulators}},
     journal = {Journal for geometry and graphics},
     pages = {141--149},
     publisher = {mathdoc},
     volume = {12},
     number = {2},
     year = {2008},
     url = {http://geodesic.mathdoc.fr/item/JGG_2008_12_2_JGG_2008_12_2_a2/}
}