| value | technique | year | title_of_literature<MAX120col.> | journal<MAX120col.> | vol | page | name<MAX80col.> |
| <0.2 | AA |
1997 | Personal Communication,SKK,Japan | | | | |
| 0.108 | ICPMS |
1998 | Personal communication,M.Watanabe,MKK,Tokyo, Japan | | | | M.Watanabe |
| 0.175 | ICPMS |
1998 | Personal communication,M.Watanabe,MKK,Tokyo, Japan | | | | M.Watanabe |
| <0.2 | AA |
1998 | Personal communication,SKK,Japan | | | | |
| 0.2 | AA |
1998 | Personal communication,SKK,Japan | | | | |
| 0.18 | HAA |
1998 | Personal communication,GSJ,Japan | | | | S.Terashima |
| <2 | EXRF |
2002 | Personal Communication, Southern Connecticut State Univ., USA | | | | T. Fleming |