Document type definition. A document type definition (DTD) is a set of markup declarations that define a document type for an SGML-family markup language (SGML, XML, HTML). A Document Type Definition (DTD) defines the legal building blocks of an XML document. It defines the document structure with a list of legal elements and attributes. A DTD can be declared inline inside an XML document, or as an external reference.
American hornbeam. The American hornbeam is a native forest understory tree in the Chicago area, making it useful for shady landscapes and naturalized or woodland gardens.New leaves emerge reddish-purple, changing to dark green, then turn yellow to orange-red in the fall, offering a kaleidoscope of color throughout the year.merican hornbeam. The American hornbeam is a native forest understory tree in the Chicago area, making it useful for shady landscapes and naturalized or woodland gardens.
A cutaneous horn, also known as cornu cutaneum, refers to a specific appearance of a skin lesion in which a cone-shaped protuberance arises on the skin caused by overgrowth of the most superficial layer of skin (epidermis).