Hayk Mirzayans Insect Museum offers training courses, and helps other scientific research centers in completion and maintenance of their insect collections. ITRD acts as the National Identification Service for governmental or non-governmental organizations, publishes various articles, reports, books, data banks and checklists of its holdings, and provides these information free of charge to all visitors. Hayk Mirzayans Insect Museum The Hayk Mirzayans Insect Museum (HMIM) is the largest insect collection in Iran with over 4 million insect specimens, including 20–25,000 local species, hundreds of primary types and paratypes, and a representative collection of exotic insects, especially tropical butterflies. In 1943, Iranian entomologist established a
Holdrian comma equal temperament are closer to Pythagorean tuning than that of 55. Thus Mercator's comma and the Holdrian comma are two distinct but related intervals. The name "Arabian comma" may be inaccurate; the comma has been employed mainly in Turkish music theory by Kemal Ilerici, and by the Turkish composer Erol Sayan. The name of this comma is "Holder koması" in Turkish. For instance, the makam "rast" (similar to the Western major scale) may be considered in terms of Holdrian commas: while in contrast, the makam "nihavend" (similar to the Western minor scale): has medium seconds between d–e, e–f, g–a, a–b,