TY  - BOOK
AU  - Macdonald, Ray
AU  - Smith, Robert L.
AU  - Thomas, John E.
TI  - Chemistry of the subalkalic silicic obsidians: by ..., Robert L. Smith and John E. Thomas
AV  - QE75 P9 no. 1523 
PY  - 1992///
CY  - Washington
PB  - U. S. Govt. Print. Off.
KW  - Obsidian
KW  - Composition
ER  -