| value | technique | year | title_of_literature<MAX120col.> | journal<MAX120col.> | vol | page | name<MAX80col.> |
| 18 | XRF |
1998 | Collaborative Study of two new GSJ Geochemical Reference Materials :Basalt JB-1b and Coal Fly Ash JCFA-1 | Analytical Results | | | S.Pierdzig and O.Krause |
| 18 | XRF |
1998 | Personal Communication,New Mexico institute of Mining & Technology | | | | Chris McKee |
| 17 | XRF |
1999 | Personal communication,Institute of Geology,Estonia | | | | T.Kiipli |
| 17 | XRF |
1994 | Personal Communication,WSU GeoAnalytical Laboratory, USA | | | | C. Knaack, S. Cornelius and P. Hooper |
| 17 | XRF |
2000 | Personarl Communication,Washington State University | | | | D. Johnson |
| 14 | OES |
1999 | Personarl Communication, Institute of Geology, Estonia | | | | T. Kiipli |
| 17.7 | EXRF |
2002 | Personal Communication, Southern Connecticut State Univ., USA | | | | T. Fleming |