Which sentence below is referenced correctly? The top is how i have referenced it, but it doesn't look right to have a citation mid sentene and then another one at the end. Further, if it is the top one, should the following sentence (using the same two authors and discussing the same thing) be re-referenced as (Beck, 1964; Fenn & Byrne, 2013) to make it clear that I am still using both of the authors? Thanks.

CBT is a short-term, structured, and solution-focused form of psychotherapy based on Beck's (1964) cognitive model of mental illness (Fenn & Byrne, 2013).

CBT is a short-term, structured, and solution-focused form of psychotherapy based on Beck's cognitive model of mental illness (Beck, 1964; Fenn & Byrne, 2013).