Tannenbaum, Beulah
Understanding light
- New York : Fawcett Publications, 1968.
- 117 páginas : il., lám., fot.
- Ladder : 2000 words ; L-54 .
This edition is for readers for whom English is a second language. It can be anyone whos has learned 2,000 words of english.
Optica
Luz