Honda Civic Hybrid 2009 Owner's Manual page 214

Protecting Your Discs
4. Small, irregular shaped discs
3-inch (8-cm) CD Triangle Shape
Can Shape Arrow Shape
208
5. Discs with scratches, dirty discs
Fingerprints, scratches, etc.
CD-R or CD-RW may not play due
to the recording conditions.
Scratches and fingerprints on the
discs may cause the sound to skip.
Recommended discs are printed
with the following logo.
Audio unit may not play the
following formats.