In was the search of the original article “The application of the formula for surface viscosity to the surface of a slowly falling droplet in the midst of a large unlimited amount of fluid which is at rest and possesses a smaller specific gravity” published by M.J. Boussinesq which was published in originally in French in the Annales de Chimie et de physique (Annals of Chemistry and of Physics) published in 1913. The paper formed the basis of the legendary Boussinesq-Scriven stress model. I found the volume of the scientific journal in a French library repository and is sharing the same here:

M.J. Boussinesq, “The application of the formula for surface viscosity to the
surface of a slowly falling droplet in the midst of a large unlimited amount
of fluid which is at rest and possesses a smaller specific gravity,” Ann. Chem.
Phys., vol. 29, pp. 357–364, 1913