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Let $\left(\cal{C},\otimes ,I\right)$ be a symmetric monoidal category (not necessarily closed) and $A$ a commutative monoid in $\cal{C}$. In his DAG III (page 95), Lurie writes:

In many cases, the category $\cal{M}od_A\left(\cal{C}\right)$ of $A$-modules in $\cal{C}$ inherits the structure of a symmetric monoidal category with respect to the relative tensor product over $A$.

Where can I find conditions, details and proofs of this (seemingly) elementary fact? (I didn't find it in the book I searched - MacLane, Barr & Wells, or in books about operads etc.)

I also need the facts that "extension of scalars" $-\otimes A$ is the left adjoint of the forgetful functor and it commutes with the tensor product. And the case when $\otimes$ distriute over the coproduct (or the bi-product).

I think I can prove most of these facts, but I want to be sure about them, and it would also be much easier to refer to them.

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This sort of stuff is shown in a lot of places that I know of for topological categories, and these things follow as degenerate cases of that, but that's probably overkill. –  Jon Beardsley 6 hours ago
    
I don't even see how can one check associativity of $\otimes_A$ if $\otimes$ doesn't preserve colimits, which is automatic in the closed case, of course. Maybe you can do it with weaker hypothesis but, do you really have a non-closed example in mind? –  Fernando Muro 6 hours ago
    
I don't need the closeness so I didn't check it. in one case I'm not even sure that it is closed. however, I think that in this case the tensor still preserve the colimit. the problem that you posed is one of the conditions I want to see. –  Yitzhak Z 6 hours ago
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I believe that having $\otimes$ distribute over reflexive coequalizers should suffice for the first paragraph, and so having $\otimes$ distribute over finite colimits should suffice for the first and second paragraphs. But I'd need some time to track down suitable references. –  Todd Trimble 6 hours ago

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