Historical narratives of manga tend to focus either on its recent, post-WWII history, or on attempts to demonstrates deep roots in the past, such as to the Chōjū-jinbutsu-giga picture scroll of the 12th and 13th centuries, or the early 19th-century Hokusai Manga. The first historical overview of Japanese comics was Seiki Hosokibara's Nihon Manga-Shi[i] in 1924. Early post-war Japanese criticism was mostly of a left-wing political nature until the 1986 publication for Tomofusa Kure's Modern Manga: The Complete Picture,[j] which de-emphasized politics in favour of formal aspects, such as structure and a "grammar" of comics. The field of manga studies increased rapidly, with numerous books on the subject appearing in the 1990s. Formal theories of manga have focused on developing a "manga expression theory",[k] with emphasis on spatial relationships in the structure of images on the page, distinguishing the medium from film or literature, in which the flow of time is the basic organizing element. Comics studies courses have proliferated at Japanese universities, and Japan Society for Studies in Cartoon and Comics (ja)[l] was established in 2001 to promote comics scholarship. The publication of Frederik L. Schodt's Manga! Manga! The World of Japanese Comics in 1983 led to the spread of use of the word manga outside Japan to mean "Japanese comics" or "Japanese-style comics".