DUO Two Factor Authentication: Using Two-Factor Without a Mobile Device / I Don't Want the DUO App on My Phone

Two-factor authentication can be used with landlines, hardware tokens and internet-based phone numbers if you do not have a mobile device. Although mobile phones, tablets and landlines are the preferred options, hardware fobs and tokens are supported.

For more information on the various methods that you can use for authentication, see the following article:
DUO Two Factor Authentication: What if I don't want to use my cell phone for authentication?