Initial information for this section when it was begun in 1996 was 
gleaned from several of the reference 
books mentioned, and from Internet sites within the United States, but not 
necessarily from within California.  Therefore any information on flight dates 
marked with a ~ should be viewed as a reference point and not as exact 
data.  When dates and habitats have been confirmed by my own or other 
Californian's sightings, or by museum specimens, I have removed the ~ next 
to that information.  Some of the web sites used most extensively 
for the initial information compilation were
  
THE ODONATA OF WASHINGTON
ODONATA OF OTTAWA DISTRICT [no longer on the web! :-(  ]
New data has been gathered from live sightings, and from these books, 
pamphlets  and museum collections:
The Dragonflies of North America, Needham and Westfall, 
1999
A list and Distributional Records of Pacific Coast Odonata, D. 
Pauslon and R. Garrison, 1979
Aquatic Insects of California, Usinger, 1968
 The Damselflies of North America, Westfall and May, 1996
The California Academy of Science's Department of Entomology
The University of California at Davis's Bohart Entomology Museum
 The UC Berkeley's CIS collection
Sonoma State University
Chico State University 
and others.