Is there any example of a real-analytic approach to evaluate a definite integral (with an elementary integrand) whose value involves Lambert W?

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I have never seen a real-analytic approach before to evaluate integrals of the form below $$\int_a^b\text{elementary function}(x)\,dx=\text{constant involving}\,W(\cdot)\,\text{in its simplest form}\tag1.$$

For instance, on MSE, all use the residue theorem:

And the same applies to some of the wider literature I have come across:

So, my question is this:

Does anyone know of a proof of an identity of the form in $(1)$ that involves only real analysis (i.e. does not assume the existence of $\sqrt{-1}$)?