Question:  Montrose Regional Airport a public airport as opposed to Luis Muñoz Marín International Airport which is what?
Related documents: [0]  [DOC] Montrose Regional Airport (IATA: MTJ, ICAO: KMTJ, FAA LID: MTJ) is a non-towered public airport on the northwest side of Montrose, in zip code 81401 in southwestern Colorado. Its two runways are at elevation 5,759 feet (1,755 m). MTJ covers 966 acres (391 ha) of land. [END] 
[1]  [DOC] Luis Muñoz Marín International Airport (IATA: SJU, ICAO: TJSJ, FAA LID: SJU) (Spanish: "Aeropuerto Internacional Luis Muñoz Marín" , Or Isla Verde International Airport/Aeropuerto Internacional de Isla Verde) is a joint civil-military international airport named for Puerto Rico's first democratically elected governor and located in suburban Carolina, Puerto Rico, 3 mi southeast of San Juan. It is the busiest airport in the Caribbean region by passenger traffic. Over 4 million passengers board a plane at the airport per year according to the Federal Aviation Administration. [END] 
Answer: 
joint civil-military international airport
joint civil-military international airport