The database Georef shows a fair amount of material on Hermosillo before
1970.  The earliest record I saw was from 1900.

Pam Enrici
Engineering, Science, and Geography librarian
Univ. of MN., Duluth (on the shores of Lake Superior)


On Wed, Jul 15, 2015 at 10:58 AM, Mark Walker <[log in to unmask]>
wrote:

> Dear Friends,
>
> I received an inquiry today from a engineer doing an environmental study
> around Hermosillo. He is looking for pre 1970s information " any historical
> topographic maps, geologic maps, aerial photographs, or land use maps for
> the Hermosillo area with a scale around 1:50,000.”
>
> I can’t find anything older than 1975. Any ideas if anything exists prior
> to 1975?
>
>
> Mark Walker
> World Map Source / Mexico Maps
> 3920 Maricopa Drive
> Santa Barbara CA 93110-1414
> 805-448-7273 mobile
> 805-687-1011 office
>