Zebrafish:

European zebrafish society - why fish research?
https://www.ezsociety.org/zebrafish-science

Reeling in the Zebrafish Cancer Models
McConnell AM, Noonan HR and Zon LI
Annu. Rev. Cancer Biol. 2021. 5:331–50
https://www.annualreviews.org/doi/10.1146/annurev-cancerbio-051320-014135

In vivo drug discovery in the zebrafish
Zon LI and Peterson RT
Nature Reviews Drug Discovery 2005. 4:35–44
https://www.nature.com/articles/nrd1606

Drosophila:

Dutchen S.
Why the fly? Reseach, Harvard Medical School Community
https://hms.harvard.edu/news/why-fly

Strange K.
Drug Discovery in Fish, Flies, and Worms. ILAR J. 2016 Dec;57(2):133-143. doi: 10.1093/ilar/ilw034. PMID: 28053067; PMCID: PMC5886320.
https://academic.oup.com/ilarjournal/article/57/2/133/2806939

Mukherjee K, Twyman RM, Vilcinskas A. Insects as models to study the epigenetic basis of disease. Prog Biophys Mol Biol. 2015 Jul;118(1-2):69-78. doi: 10.1016/j.pbiomolbio.2015.02.009. Epub 2015 Mar 14. PMID: 25778758.
https://www.sciencedirect.com/science/article/pii/S0079610715000346?via%3Dihub