Section 28C. Whenever there is reasonable cause to believe that a book which is being disseminated, or is in the possession of any person who intends to disseminate the same, is obscene, the attorney general, or any district attorney within his district, shall bring an information or petition in equity in the superior court directed against said book by name. Upon the filing of such information or petition in equity, a justice of the superior court shall, if, upon a summary examination of the book, he is of opinion that there is reasonable cause to believe that such book is obscene, issue an order of notice, returnable in or within thirty days, directed against such book by name and addressed to all persons interested in the dissemination thereof, to show cause why said book should not be judicially determined to be obscene. Notice of such order shall be given by publication once each week for two successive weeks in a daily newspaper published in the city of Boston and, if such information or petition be filed in any county other than Suffolk county, then by publication also in a daily newspaper published in such other county. A copy of such order of notice shall be sent by registered mail to the publisher of said book, to the person holding the copyrights, and to the author, in case the names of any such persons appear upon said book, fourteen days at least before the return day of such order of notice. After the issuance of an order of notice under the provisions of this section, the court shall, on motion of the attorney general or district attorney, make an interlocutory finding and adjudication that said book is obscene, which finding and adjudication shall be of the same force and effect as the final finding and adjudication provided in section twenty-eight E or section twenty-eight F, but only until such final finding and adjudication is made or until further order of the court. It shall be an affirmative defense under this section if the evidence proves that the defendant was a bona fide school, museum or library, or was acting in the course of his employment as an employee of such organization or of a retail outlet affiliated with and serving the educational purpose of such organization.