Author
Akademii͡a nauk SSSR. Quantum Bureau
1
American Association of Physics Teachers
1
American Council of Science Teachers
2
American Science Teachers Association
2
Illinois Association of Chemistry Teachers
2
National Council of Teachers of Mathematics
1
National Science Teachers Association
Rossiĭskai͡a akademii͡a nauk. Quantum Bureau
1
Thomson Gale (Firm)
1