Period 4 element (English Wikipedia)

"Calcium". Human Vitamin and Mineral Requirements (Report). Rome, Italy: FAO Information Division Publishing and Multimedia Service. 2002. Retrieved 2012-08-14.

jlab.org (Global: low place; English: low place)

education.jlab.org

Office of Science Education. "The Element Potassium". It's Elemental. Newport News: Jefferson Science Associates. Retrieved 2012-08-14.

lenntech.com (Global: low place; English: low place)

"Potassium - K". Lenntech. 1998. Retrieved 2012-08-14.

nih.gov (Global: 4^th place; English: 4^th place)

pubmed.ncbi.nlm.nih.gov

Srivastava, A. K. (2000). "Anti-diabetic and toxic effects of vanadium compounds". Molecular and Cellular Biochemistry. 206 (206): 177–182. doi:10.1023/A:1007075204494. PMID 10839208. S2CID 8871862.
Makhlynets, Olga; Boal, Amie K.; Rhodes, Delacy V.; Kitten, Todd; Rosenzweig, Amy C.; Stubbe, JoAnne (2014-02-28). "Streptococcus sanguinis class Ib ribonucleotide reductase: high activity with both iron and manganese cofactors and structural insights". The Journal of Biological Chemistry. 289 (9): 6259–6272. doi:10.1074/jbc.M113.533554. ISSN 1083-351X. PMC 3937692. PMID 24381172.
Caputo, Gregory A.; Vaden, Timothy D.; Calabro, Anthony; Lee, Joshua Y.; Kohn, Eric M. (December 2018). "Heme Dissociation from Myoglobin in the Presence of the Zwitterionic Detergent N,N-Dimethyl-N-Dodecylglycine Betaine: Effects of Ionic Liquids". Biomolecules. 8 (4): 126. doi:10.3390/biom8040126. PMC 6315634. PMID 30380655.

ncbi.nlm.nih.gov

Makhlynets, Olga; Boal, Amie K.; Rhodes, Delacy V.; Kitten, Todd; Rosenzweig, Amy C.; Stubbe, JoAnne (2014-02-28). "Streptococcus sanguinis class Ib ribonucleotide reductase: high activity with both iron and manganese cofactors and structural insights". The Journal of Biological Chemistry. 289 (9): 6259–6272. doi:10.1074/jbc.M113.533554. ISSN 1083-351X. PMC 3937692. PMID 24381172.
Caputo, Gregory A.; Vaden, Timothy D.; Calabro, Anthony; Lee, Joshua Y.; Kohn, Eric M. (December 2018). "Heme Dissociation from Myoglobin in the Presence of the Zwitterionic Detergent N,N-Dimethyl-N-Dodecylglycine Betaine: Effects of Ionic Liquids". Biomolecules. 8 (4): 126. doi:10.3390/biom8040126. PMC 6315634. PMID 30380655.

science.co.il (Global: low place; English: low place)

"List of Elements of the Periodic Table – Sorted by Abundance in Earth's crust". Science.co.il. Retrieved 2012-08-14.

semanticscholar.org (Global: 11^th place; English: 8^th place)

api.semanticscholar.org

Srivastava, A. K. (2000). "Anti-diabetic and toxic effects of vanadium compounds". Molecular and Cellular Biochemistry. 206 (206): 177–182. doi:10.1023/A:1007075204494. PMID 10839208. S2CID 8871862.

tutorvista.com (Global: low place; English: low place)

"Elements in the Modern Periodic Table, Periodic Classification of Elements". Tutorvista.com. Archived from the original on 26 January 2018. Retrieved 2012-08-14.

web.archive.org (Global: 1^st place; English: 1^st place)

"Elements in the Modern Periodic Table, Periodic Classification of Elements". Tutorvista.com. Archived from the original on 26 January 2018. Retrieved 2012-08-14.

worldcat.org (Global: 5^th place; English: 5^th place)

search.worldcat.org

Makhlynets, Olga; Boal, Amie K.; Rhodes, Delacy V.; Kitten, Todd; Rosenzweig, Amy C.; Stubbe, JoAnne (2014-02-28). "Streptococcus sanguinis class Ib ribonucleotide reductase: high activity with both iron and manganese cofactors and structural insights". The Journal of Biological Chemistry. 289 (9): 6259–6272. doi:10.1074/jbc.M113.533554. ISSN 1083-351X. PMC 3937692. PMID 24381172.

Period 4 element (English Wikipedia)

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ncbi.nlm.nih.gov

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