The Spanish Civil War - pg. 68

For a long war it looked as if the Republic had the advantage:
the large cities with their industry and manpower, most of the
navy and merchant marine, two-thirds of mainland territory,
the gold reserves, and the citrus fruit export trade from Valencia,
which was the country's largest foreign currency earner. However,
the Nationalists were more than compensated by help from outside
Spain. Their primary supply of recruits for sometime was Riffian tribes.
Hitler and Mussolini were to provide military, naval, air, logistical
and technical support, while American and British business interests
supplied vital credits and oil.