El Diario La Prensa
El Diario La Prensa is the largest and the oldest Spanish-language daily in the United States.
The newspaper was created in 1963 through the merger of "El Diario de Nueva York" (established in 1947) and "La Prensa" (established as a weekly in 1913 and converted into a daily in 1918). In 2004, under the largest Spanish-language newspaper publisher in the United States, it merged with the Los Angeles-based "La Opinión" and is calling itself “el campeón de los Hispanos” (= “the champion of the Hispanics”.
The daily and Sunday stories of "Mandrake the Magician" were featured inside the newspaper from (at least) between 1963 and 1974, more precise dates remain to be determined.
Samples
issue May 2, 1963 / daily strip 1963 04 23, story "Smuggler's Luck".
detail of issue June 21, 1963 / daily strip 1963 06 03, story "The Giant Toothache" (detail / see creator names shifted).
issue January 1, 1967 / Sunday page 1966 12 04, story "The Astro Pirates".