A simple proof of the rectilinear art gallery theorem

Reference:

Heikki Mannila and D. Wood. A simple proof of the rectilinear art gallery theorem. International Journal of Computer Mathematics, 17:141–149, 1985.

Suggested BibTeX entry:

@article{mw1,
    author = {Heikki Mannila and D. Wood},
    journal = {International Journal of Computer Mathematics},
    pages = {141-149},
    title = {A simple proof of the rectilinear art gallery theorem},
    volume = {17},
    year = {1985},
}