The image is signed on the bottom right and seems to be cut off on some copies of this issue.
Script credit reported at http://www.copyrightencyclopedia.com. Shinner is called 'Shiner' and Freedland is called 'Friedland' at various points in the story.
The signature on this story is dated '77'. The signature is 'elias & DEMETRIO', probably by a single letterer. There are various claims about the identity of 'Elias', including that he provided the script. However, it seems most likely this is Spanish artist Alfredo Elías Mondeja (who did Simba in 'Jaimito').
The signature on this story is dated '79'.
This story doesn't seem to be from the usual Spanish source. It is not the standard 16 pages.
This feature has been created from the upper half of 'How to Draw Tarzan's Animals' from Limited Collectors' Edition (DC, 1972 series) #C-29 ([August-September] 1974). It does not appear to have been sourced directly from DC.