Lancet study for UKCTOCS -2021
https://www.thelancet.com/journals/lancet/article/PIIS0140-6736(21)00731-5/fulltext
and 2015
https://www.thelancet.com/journals/lancet/article/PIIS0140-6736(15)01224-6/fulltext

Puerto Rico practice
https://www.hindawi.com/journals/bmri/2014/920915/

US Preventive services taskforce
https://www.uspreventiveservicestaskforce.org/uspstf/recommendation/ovarian-cancer-screening

NHS advice on ovarian cancer symptoms https://www.nhs.uk/conditions/ovarian-cancer/