Rotary-Phone6.mp3
===
Creator: David English
Source: http://www.beepzoid.com/old-phones/
License: unknown

Ping1.mp3
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Creator: CameronMusic
Source: https://soundcloud.com/freefilmandgamemusic/ping-1?in=freefilmandgamemusic/sets/free-notification-sounds-and
License: cc 3.0, http://creativecommons.org/licenses/by/3.0/