Can anyone give me the name of a source on identifying cerion shells?

Emeritus Professor of PhysicsOglethorpe University, Atlanta, GAebooks at
 https://www.smashwords.com/books/search?query=John+Cramerpaperback books at
 https://www.lulu.com/shop/search.ep?keyWords=john+a.+cramer&type=&pn=2

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