Comparison of the variations of sunspot number, number of sunspot groups, and sunspot area, 1875-2013 / Robert M. Wilson.
Series InformationNASA technical paper
- Physical Description: 1 online resource (viii, 23 pages) : illustrations.
- Publisher: Huntsville, Alabama : National Aeronautics and Space Administration, Marshall Space Flight Center, April 2014.
Title from title screen (viewed March 12, 2015).
|Bibliography, etc. Note:||
Includes bibliographical references (pages 21-23).
|Funding Information Note:||
Sponsored by National Aeronautics and Space Administration M-1381