Generalizations of Guillera-Sondow's double integral formulas
  We evaluate certain multidimensional integrals in terms of the Lerch transcendent function $\Phi$, generalizing Guillera-Sondow's formulas. As an application, we get new representations of classical constants like Euler's constant $\gamma$ and $\ln(4/\pi)$. 
Sergey Zlobin