This inheritance list is sorted roughly, but not completely, alphabetically:

CID3_Tag::ConstIterator
CID3_Field	The representative class of an ID3v2 field
CID3_FieldImpl
CID3_FieldDef
CID3_Flags
CID3_Frame	The representative class of an id3v2 frame
CID3_FrameDef
CID3_FrameImpl
CID3_FrameInfo	Provides information about the frame and field types supported by id3lib
CID3_Header
CID3_FrameHeader
CID3_TagHeader
CID3_Reader
CID3_IStreamReader
CID3_IFStreamReader
CID3_MemoryReader
CID3_Tag	The representative class of an id3 tag
CID3_TagImpl
CID3_Writer
CID3_IOStreamWriter
CID3_FStreamWriter
CID3_MemoryWriter
CID3_OStreamWriter
CID3_OFStreamWriter
CID3_Header::Info
CID3_Tag::Iterator
CMp3_Headerinfo
CMp3Info