TY  - GEN
TI  - Permanence - durability of the book. 
PY  - 1964///-1967.
CY  - Virginia : 
PB  - W. J. Barrow Reseach Laboratory, 
N1  - Catalogación preliminar; Contiene : 1. Test data of naturally aged papers II - 2. Spray deacidificación III - 3. Strength and other characteristics of book papers 1800-1899 V.
ER  -