This industry comprises establishments known as publishers (except newspaper, magazine, book, directory, mailing list, and music publishers). These establishments may publish works in print or electronic form. Establishments publishing exclusively on the Internet are classified in Industry 516110, Internet Publishing and Broadcasting; Establishments known as newspaper publishers are classified in Industry 511110, Newspaper Publishers; Establishments known as magazine and other periodical publishers are classified in Industry 511120, Periodical Publishers; Establishments known as book publishers are classified in Industry 511130, Book Publishers; Establishments primarily engaged in publishing directories and mailing lists are classified in Industry 511140, Directory and Mailing List Publishers; Establishments known as music publishers are classified in Industry 512230, Music Publishers; and Establishments primarily engaged in manufacturing manifold business forms are classified in Industry 323110, Printing.