arXiv.org e-Print Archive, Science Direct
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Springer Nature, ACS Publications
Wiley Online Library
Surfave and Interface Analysis
Journal of Electron Spectroscopy and Related Phenomena
Science Central
Science Magazine ScienceDaily
Physics World
The XPS Library
The International XPS Database
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XPS International
Lasurface: XPS,AES,UPS and ESCA.
Surface Science Western
Physics & Astronomy Online Reference and Education
NIST Chemistry WebBook ThoughtCo. On-Line Books
The Universal Library MIT's OpenCourseWare
Learn Engineering
USA Today
X-Ray Photoelectron Spectroscopy Learning Center