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Creation Date 

1. Before 1957  (1,416,197)
2. 1957 To 1973  (1,678,571)
3. 1974 To 1990  (4,846,441)
4. 1991 To 2008  (17,961,023)
5. After 2008  (45,603,924)
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New Records 

1. New From Last Week  (21,762)
2. New From Last Month  (242,552)
3. New From Last 3 Month  (809,328)
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Resource Type 

1. Articles  (39,245,942)
2. Newsletter Articles  (9,309,127)
3. Book Chapters  (6,169,041)
4. Newspaper Articles  (4,903,330)
5. magazinearticle  (3,077,777)
6. Reviews  (2,503,584)
7. Thesises (postgraduate)  (1,249,283)
8. Reports  (1,226,568)
9. Books  (1,073,118)
10. Web Resources  (647,097)
11. Conference Proceedings  (555,242)
12. References  (492,588)
13. Text Resources  (256,343)
14. Patents  (172,071)
15. Images  (125,897)
16. Datasets  (47,323)
17. Audio  (32,826)
18. Government Documents  (27,658)
19. Journals  (25,714)
20. Archival Material / Manuscripts  (10,998)
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Subject 

1. Science & Technology  (19,425,038)
2. Life Sciences & Biomedicine  (14,057,655)
3. Humans  (9,630,272)
4. Female  (5,364,241)
5. Male  (5,244,999)
6. Physical Sciences  (3,723,053)
7. Animals  (3,533,010)
8. Social Sciences  (3,437,560)
9. Biological And Medical Sciences  (3,408,011)
10. Technology  (3,201,715)
11. Adult  (3,144,027)
12. Middle Aged  (2,821,960)
13. Medical Sciences  (2,300,601)
14. Aged  (2,064,649)
15. Studies  (1,805,812)
16. Engineering  (1,614,530)
17. Chemistry  (1,570,271)
18. Physics  (1,477,653)
19. Exact Sciences And Technology  (1,382,969)
20. Adolescent  (1,295,042)
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Author/Creator 

1. Munro, Ian  (248)
2. Beaujot, Roderic  (172)
3. Division on Earth and Life Studies  (164)
4. National Research Council (U.S.)  (115)
5. National Research Council  (104)
6. Pontifical Institute of Mediaeval Studies  (77)
7. Chatton, Walter  (66)
8. Canadian Corporation for Studies in Religion  (58)
9. Board on Life Sciences  (41)
10. Commission on Life Sciences  (39)
11. National Research Council Staff  (35)
12. National Academy of Sciences  (28)
13. Board on Chemical Sciences and Technology  (25)
14. Commission on Geosciences, Environment and Resources  (24)
15. Board on Environmental Studies and Toxicology  (23)
16. Division on Engineering and Physical Sciences  (17)
17. Mciver, Don  (16)
18. Institute for Laboratory Animal Research  (14)
19. Chemical Sciences Roundtable  (13)
20. Project Muse  (13)
21. Committee on Toxicology  (12)
22. Institute of Medicine  (12)
23. Space Studies Board  (11)
24. Board on Earth Sciences and Resources  (10)
25. McIver, Don  (10)
26. Board on Agriculture and Natural Resources  (10)
27. Bennett, Paul W  (9)
28. International Association of Centers for Federal Studies  (9)
29. Munro, Ian  (9)
30. Rand Corporation  (9)
31. Commission on Physical Sciences, Mathematics, and Applications  (9)
32. Beaujot, Roderic  (8)
33. Chatton, Walter  (8)
34. Board on Environmental Studies and Toxicology Staff  (8)
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Databases 

1. ProQuest Central  (36,607,932)
2. MEDLINE  (13,181,300)
3. DOAJ Directory of Open Access Journals  (9,582,945)
4. ROAD: Directory of Open Access Scholarly Resources  (7,028,842)
5. GFMER Free Medical Journals  (6,937,957)
6. PubMed Central  (6,353,396)
7. HighWire Press (Free Journals)  (2,128,749)
8. ProQuest One Psychology  (1,779,002)
9. Open Access: Wiley-Blackwell Open Access Journals  (1,371,711)
10. Springer_OA刊  (1,306,940)
11. Ebook Central - Academic Complete  (1,233,256)
12. Free E- Journals  (1,116,464)
13. Education Resources Information Center (ERIC)  (724,486)
14. JSTOR Early Journal Content Free  (554,901)
15. arXiv.org  (506,728)
16. Open Access: Nature Open Access  (473,051)
17. Open Access: IOP Publishing Free Content  (401,607)
18. Hyper Article en Ligne (HAL) (Open Access)  (388,654)
19. Taylor & Francis Open Access  (388,142)
20. Public Library of Science (PLoS) Journals Open Access  (375,449)
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Language 

1. English  (66,542,540)
2. Japanese  (3,207,518)
3. German  (1,224,926)
4. Chinese  (1,134,196)
5. French  (516,781)
6. Spanish  (465,603)
7. Portuguese  (394,113)
8. Russian  (267,856)
9. Korean  (226,839)
10. Polish  (137,790)
11. Swedish  (120,875)
12. Norwegian  (109,492)
13. Italian  (80,009)
14. Persian  (75,119)
15. Turkish  (71,991)
16. Croatian  (67,379)
17. Arabic  (56,311)
18. Czech  (41,183)
19. Dutch  (37,530)
20. Indonesian  (37,442)
21. Danish  (23,193)
22. Ukrainian  (20,898)
23. Hebrew  (4,396)
24. Estonian  (3,475)
25. Byelorussian  (461)
26. Swahili  (125)
27. Romany  (1)
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Journal Title 

1. arXiv.org  (332,542)
2. Business Wire  (241,993)
3. Chicago Tribune  (188,049)
4. M2 Presswire  (307,009)
5. New York Times  (228,854)
6. Plos One  (303,124)
7. Pr Newswire  (357,882)
8. The Los Angeles Times  (197,090)
9. The New York Times  (253,668)
10. The Washington Post  (233,737)
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