Ross, Wendy. «The Rise-but rarely the fall-of the Elevator». The Washington Post. Archivado desde el original el 17 de julio de 2021. Consultado el 14 de julio de 2021. «The Otis brothers had installed the first two successful electric elevators in the Demarest Building in New York in 1889».
web.archive.org
Ross, Wendy. «The Rise-but rarely the fall-of the Elevator». The Washington Post. Archivado desde el original el 17 de julio de 2021. Consultado el 14 de julio de 2021. «The Otis brothers had installed the first two successful electric elevators in the Demarest Building in New York in 1889».
