Harvard University. Laboratory for Computer Graphics and Spatial Analysis. SYMPAP user's reference manual. The Laboratory.
Chicago-viite (17. p.)Harvard University. Laboratory for Computer Graphics and Spatial Analysis. SYMPAP User's Reference Manual. [s.l.]: The Laboratory.
MLA-viite (9. p.)Harvard University. Laboratory for Computer Graphics and Spatial Analysis. SYMPAP User's Reference Manual. The Laboratory.
Varoitus: Nämä viitteet eivät aina ole täysin luotettavia.