End punctuations such a full stops (.), exclamation points (!) and question marks (?) are almost never used in combination with one another. If a reference title ends in a question mark or an exclamation point, this mark or point will take place of the full stop that would have otherwise appear after the title.
In the APA 7th Referencing example below, the question mark at the end of the title takes the place of the full stop which would have otherwise been inserted.
Correct:
Lane, D. (2020). Homelessness: A “cause of the causes” of cardiovascular disease? Heart, 106(19), 1456–1457. https://doi.org/10.1136/heartjnl-2020-317224
Incorrect:
Lane, D. (2020). Homelessness: A “cause of the causes” of cardiovascular disease?. Heart, 106(19), 1456–1457. https://doi.org/10.1136/heartjnl-2020-317224
