WikiTree uses "ref tags" to create what in publishing circles is a "call out" (a superscript number) & whatever is added by the ref tag is collected by <references /> - which, per WikiTree guidelines, is immediately below == Sources == (one of two required second-level headings; one of four allowed 2nd-level headings - see [[Help: Biographies#Text_Sections]]).
Since bulleted sources are below <references /> they're not technically "end notes" or "footnotes". WikiTree calls them "inline citations". If you add them after <references />, they won't be clickable (see [this page]).
