| value | technique | year | title_of_literature<MAX120col.> | journal<MAX120col.> | vol | page | name<MAX80col.> |
| 0.24 | INAA |
1994 | Personal Communication, The Open University, UK | | | | P.Potts |
| 0.24 | ICPMS |
1994 | Personal communication, National Geophysical Research Institute | | | | V.Balaram |
| 1.07 | INAA |
1994 | Personal communication,Lund Univ., Sweeden | | | | Zoltan Solyom |
| 0.22 | ICPMS |
1994 | Personal communication, National Geophysial Research Instituti, India | | | | V. Balaram |
| 0.24 | ICPMS |
1998 | Personal communication,M.Watanabe,MKK,Tokyo, Japan | | | | M.Watanabe |
| 0.19 | ICPMS |
1998 | Personal communcation,Universite de Liege,Belgium | | | | I.Roelandts |
| 0.21 | ICPMS |
1994 | Personal Communication,WSU GeoAnalytical Laboratory, USA | | | | C. Knaack, S. Cornelius and P. Hooper |
| 0.21 | ICPMS |
2000 | Personarl Communication,Washington State University | | | | D. Johnson |
| <5 | EXRF |
2002 | Personal Communication, Southern Connecticut State Univ., USA | | | | T. Fleming |