Postcard sent to John J. Herrera, Mike, and Shep in Houston, Texas from John's son, Douglas M. Herrera in Mexico. Text: "23 Sept 68, Dear Dad, Mike, Shep, San Luis is a pretty pace, muchas bonitas mujeres but I'm itching to get to la Ciudad D. F. So I'm catching the 11:30 A.M. bus out tomorrow so I can register for classes & begin the next day. Having a Corona on you all fellas. Wish me luck, I need it. DMH." The front of the postcard has images of four buildings in San Luis Potosi, identified on the reverse as Teatro de La Paz/La Paz Theatre, Plaza de los Fundadores/The Founders Square, La Caja del Agua/The Water Box, and Palacio de Gubierno/Government Palace.

Postcard to John J. Herrera and his wife Olivia from their son, Douglas M. Herrera. The postcard was mailed from Merida, Mexico to Houston, Texas and details the next portion of Douglas's journey and receipt of his father's telegram. The front image is of a hackney coach with "mestizas", two women standing in traditional dress in front of Saint John's Temple.

Postcard to John J. Herrera from Terry Serna that reads: "Hi Johnny! Still in the convention mood. Having a ball before returning to the grind! Terry Serna." The front of the postcard has the image of of a waterfall with people in the foreground. The image is identified on the back of the postcard as "Cascada La Cola De Caballo, Horsetail Falls near Monterrey. Monterrey, N. L., Mexico"

Postcard to John J. Herrera from El Rey Bonito is postmarked Monterrey, Mexico. The image on the front of the card is a building that is identified on the reverse of the card as "Palacio de Gobierno. Monterrey, N.L., Mexico." The handwritten notes reads, "Greeting to you Mr. Herrera. Regards to Miss Hernandez Mr. Fielder y al abogados Pansas El Lic Tazzo el chofer d Welch Ortiz El Rey Bonito".