doubt as to ownership. {Sidenote: Anonymous works} There is no specific reference in the new American code as to anonymous or pseudonymous works, except as to duration of copyright. In practice, the Copyright Office assumes that the applicant for the entry of an anonymous or pseudonymous work is the qualified and legal author or proprietor, and any disputed question of fact would ultimately be decided by the courts. {Sidenote: Joint authorship} There may be joint authorship in a work of common design, in which case the joint authors will become owners in common of the undivided property; but mere alterations or work on specific parts could not justify claim to more than such alterations or parts. The copyright would naturally be entered in both names, but as one copyright; it was held in 1902, in Mifflin _v._ Dutton, by the U. S. Supreme Court, that "there cannot be duplicate copyrights of the same book in different names." If one of the joint authors and not the other should apply for entry, the Copyright Office would in practice probably record the copyright claim on the presumption that the author was acting in the common interest; but if two joint authors applied simultaneously and severally, the question of ownership would have to be settled by the courts. {Sidenote: Corporate bodies} A corporate body, even though not incorporated under statute, is considered an author in the case of its own proceedings or similar publications, and in 1903 Justice Holmes rendered the decision of the U. S. Supreme Court in the case of Bleistein _v._ Donaldson Lith. Co., though the court was divided on the subject, that a copyright taken in the name of the Courier Lithographing Company, which was only the trade name of the complainant, was valid. {Sidenote: Posthumous works} In the case of posthumous works, the person entitled to copyright would be the executor, administrator, or the heirs of the author, and the owner of an unpublished manuscript could probably enter and maintain copyright in the absence of other legal claimant. {Sidenote: The Peary cases} {Sidenote: Opposing decisions}