Where can I find some background information on photogrammetry and/or the algorithms used in PhotoModeler?

Here are some references that cover photogrammetry in general:

Books

* Close Range Photogrammetry: Principles, Methods and Applications, T.Luhmann, S. Robson, S. Kyle, I. Harley, 2006, Whittles Publishing.

* The Manual of Photogrammetry, 5th Ed., C. McGlone, E. Mikhail, J. Bethel, R. Mullen, 2004, American Society of Photogrammetry and Remote Sensing.

* Introduction to Modern Photogrammetry, E. Mikhail, J. Bethel, J. McGlone, 2001, John Wiley & Sons.

* Close Range Photogrammetry and Machine Vision, K. Atkinson, 1996, Whittles Publishing.

* Non-Topographic Photogrammetry, 2nd Ed., H. Karara, 1989, American Society of Photogrammetry and Remote Sensing.

Journals

* Photogrammetric Record: http://onlinelibrary.wiley.com/journal/10.1111/(ISSN)1477-9730/

* ISPRS Journal of Photogrammetry and Remote Sensing: http://www.elsevier.com/locate/isprsjprs

Web pages

www.asprs.org

www.isprs.org

cipa.icomos.org

Some other links from our website:  http://www.photomodeler.com/resources.html