| value | technique | year | title_of_literature<MAX120col.> | journal<MAX120col.> | vol | page | name<MAX80col.> |
| 10 | OES |
1990.04 | Personal communication, Geological Survey of India | | | | B.G.Rao |
| 4 | XRF |
1990.04 | Personal communication, Govern. Chem. Lab., Brisbane, Australia | | | | H.A.Olszowy, J.Hegarty, P.Smith, R.Sumner, S.Mckeo |
| <10 | OES |
1990.05 | Personal Communication, U.S. Geological Survey, Lakewood | | | | J.S.Kane, J.G.Crock, P.H.Briggs and D.L.Fey |
| 2.3 | FAA |
1990 | Personal communication, U.S. Geological Survey | | | | H.N.Elsheimer and |
| 2 | XRF |
1996 | Personal communication, Bremen Univ., Germany | | | | M.Zuther |
| 2.1 | HAA |
1998 | Personal communication,GSJ,Japan | | | | S.Terashima |
| 2.14 | ICPMS |
1998 | Personal communication,National Institute for Environmental Studies, Japan | | | | J.Yoshinaga |
| 3 | OES |
1999 | Personarl Communication, Institute of Geology, Estonia | | | | T. Kiipli |