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You

For the special case of symmetric monoidal $(\infty,1)$-categories, you can find it in chapter 2, especially definition 2.0.0.7 of:

Jacob Lurie, Higher Algebra, pdf (with 950 pages, sic!)

However Segal spaces are not used here, since this is the more general definition of a symmetric monoidal $\infty$-category. Remark that the definition is motivated before.

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You can find it in chapter 2, especially definition 2.0.0.7 of:

Jacob Lurie, Higher Algebra, pdf (with 950 pages, sic!)

However Segal spaces are not used here, since this is the more general definition of a symmetric monoidal $\infty$-category. Remark that the definition is motivated before.