Research on ingredients listed:
Chamomile:
https://www.tandfonline.com/doi/abs/10.3109/09637486.2011.627841
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3210003/
https://scidar.kg.ac.rs/handle/123456789/10663
https://foundationsofherbalism.com/pdf/7.pdf
Fennel:
https://www.sciencedirect.com/science/article/pii/B978085709040950014X
https://www.sciencedirect.com/science/article/pii/B9780081026595000197
https://www.sciencedirect.com/science/article/pii/B9780123756886100556
https://www.tandfonline.com/doi/abs/10.3109/09637486.2011.627841
Anise:
https://www.tandfonline.com/doi/abs/10.3109/09637486.2011.627841
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4146877/
https://www.tandfonline.com/doi/full/10.1080/23312025.2019.1673688
https://scindeks.ceon.rs/Article.aspx?artid=0455-62241434003A
https://link.springer.com/chapter/10.1007/978-1-4614-4310-0_8
https://link.springer.com/article/10.1007/s13197-018-3109-y
http://umkeprints.umk.edu.my/6632/
Orange peel:
https://link.springer.com/chapter/10.1007/978-3-030-98760-2_7
https://www.sid.ir/paper/181410/en
https://www.sciencedirect.com/science/article/pii/S1319562X22001462
Peppermint:
https://www.aafp.org/afp/2007/0401/p1027.html
https://link.springer.com/article/10.1007/S10620-015-3858-7
https://link.springer.com/article/10.1007/s10620-009-0854-9
https://link.springer.com/article/10.1007/s10620-012-2194-4
Licorice:
https://www.tandfonline.com/doi/full/10.1080/13880209.2016.1225775
https://www.sciencedirect.com/science/article/pii/B9780128212325000082
https://europepmc.org/article/med/26427098
https://europepmc.org/article/med/20209894
https://www.chalcogen.ro/947_Rodino.pdf
https://www.frontiersin.org/articles/10.3389/fphar.2020.00869/full
https://www.sciencedirect.com/science/article/abs/pii/S1674638417601163
https://www.scielo.br/j/bjid/a/BPQFSqGF6YK6hdtdTRXBbsC/abstract/?lang=en
https://www.sciencedirect.com/science/article/pii/B9780128054130000144
https://link.springer.com/article/10.1007/s10620-012-2495-7
https://link.springer.com/chapter/10.1007/978-3-030-04408-4_1