Scientific References

1. Susan Mayor, “Erection Hardness Scale Proves Effective In Assessing Erection Quality”, 28 Mar 2008,
https://www.medicalnewstoday.com/articles/101961.php

2. Cohen AJ., Bartlik B., “Ginkgo biloba for antidepressant-induced sexual dysfunction” 1998 Apr-Jun
https://www.ncbi.nlm.nih.gov/pubmed/9611693

3. UroToday, Volume 3 2010, “Safety and Efficacy of the Herbal Drug Hypericum Perforatum for the Treatment of Premature Ejaculation”,
https://www.urotoday.com/volume-3-2010/vol-3-issue-3/36187-safety-and-efficacy-of-the-herbal-drug-hypericum-perforatum-for-the-treatment-of-premature-ejaculation-2229105.html

4. Chemistry of amino acids and protein structure. (n.d.)
www.khanacademy.org/test-prep/mcat/biomolecules/amino-acids-and-proteins1/a/chemistry-of-amino-acids-and-protein-structure

5. Ciacci, C., Franceschi, F., Purchiaroni, F., Capone, P., Buccelletti, F., Iacomini, P., ... Gasbarrini, G. (2011). "Effect of beta-glucan, inositol and digestive enzymes in GI symptoms of patients with IBS." European Review for Medical and Pharmacological Sciences, 15(6), 637–643
www.europeanreview.org/article/957

6. Rao, R., & Samak, G., 2012, January, “Role of glutamine in protection of intestinal epithelial tight junctions.” Journal of Epithelial Biology & Pharmacology
www.ncbi.nlm.nih.gov/pmc/articles/PMC4369670/

7. Crawford C., Wang YH,, Avula B., Clin Toxicol (Phila),  2020 Jan 28 “The scoop on brain health dietary supplement products containing huperzine” A.
https://www.ncbi.nlm.nih.gov/pubmed/31990212

8.  Aids Council, June 4, 2015, “Nootropics for improved sexual performance
http://www.aidscouncil.org.au/nootropics-for-improved-sexual-performance/

9. Nicole Prause, Jaymie Park, Shannon Leung and Geoffrey Miller,  PLoS One, 2015, “Women's Preferences for Penis Size: A New Research Method Using Selection among 3D Models
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4558040/

10. Harvard Health Publishing, Harvard Medical School, “5 natural ways to overcome erectile dysfunction
https://www.health.harvard.edu/mens-health/5-natural-ways-to-overcome-erectile-dysfunction

11. Weller, Chris, “Nitric Oxide Beads Beat Out Viagra In Treating Erectile Dysfunction”, in ”Medical Daily”, October, 2015:
http://www.medicaldaily.com/nitric-oxide-beads-beat-out-viagra-treating-erectile-dysfunction-258683

12. Gruss, William, “Nobel Prize Discovery Proves You Can Defeat Impotence Now”, in “Natural Health News Report”, May, 2012:
http://www.naturalhealthnewsreport.com/page/nhn/articles/specialreport/2012-05-15-045.html

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