EAGLE arduino-xxxx.lib used in .Zip boards and schematics

Hi there
In the .ZIP I downloaded for Board and Schematic files in EAGLE I noticed the these are using arduino-connectors.lib, arduino-ics.lib and many more. So I tried to find these libraries but was not successful.
Has someone a hint where to find them. Tried ADAFRUIT and element14 but did not find them.
Regards, harald