Ready References
A Guide to Backyard Astronomy
Using a Naked-Eye Starmap
Star-Finding With a Planisphere
AAVSO Publications and Periodicals
Optical Instruments
Laboratory Optical Work
The Severity of an Earthquake
Ready References A Guide to Backyard Astronomy 
Using a Naked-Eye Starmap Star-Finding With a Planisphere AAVSO Publications and Periodicals 
Optical Instruments Laboratory Optical Work The Severity of an Earthquake