Gibbs ([1889, p. 140](https://archive.org/stream/americanjourna3371889newh#page/140)): $ \qquad \dfrac{d\,\log\mathrm V}{d\,\log p} = - \dfrac{d\,\log n}{d\,\log\lambda} $ Gauss ([1876, p. 401](https://archive.org/stream/werkecarlf03gausrich#page/n414)): $ \qquad \dfrac{\mathrm{d\,d}\,P}{(\mathrm{d}\log\eta)^2}= \dfrac{\mathrm d\,P}{\mathrm d\log y} $ Legendre ([1826, p. 466](https://archive.org/stream/bub_gb_c4M_AAAAcAAJ#page/n491)): $ \quad \dfrac{d\,l\,\Gamma a}{da} + \dfrac{d\,l\,\Gamma(\frac12+ a)}{d(\frac12+ a)} - \dfrac{2d\,l\,\Gamma(2a)}{d(2a)} = -2l\,2 $ L’Huilier ([1795, p. 96](https://archive.org/stream/principiorumcal00lhugoog#page/n136)): $ \qquad \dfrac{d.a^{\mathrm z}}{d.\log.z}= A.a^{\mathrm z} $