MELA's PERSIAN CATALOGING MANUAL
The present official calendar in Iran is known as the Jalālī calendar. It is widely used throughout the country, by publishers and the CIP Service of the National Library. Dates from this calendar are normally indicated in publications by the words hijrī shamsī (هجری شمسی) or the abbreviation H. Sh. (ه.ش.). In the absence of a specific indication of the calendar, a month appearing with the date can help with identification.
The web-based tool http://www.payvand.com/calendar/ is recommended for converting Jalālī calendar dates into Gregorian.
The Islamic calendar was used in Iran until the end of 19th century. Sometimes Iranian publications use this calendar, especially when giving birth and death dates of classical Muslim authors in the CIP. Dates from this calendar are normally indicated in publications by the terms qamarī (قمری) or hijrī qamarī, (هجری قمری) or the abbreviations Q. ( .ق) or H.Q. (.ه.ق).
There are number of web-based converters from the Islamic Calendar into the Gregorian calendar or vice versa. It is important to use a converter which allows you to specify a month as years in this calendar normally span two years. MELA hosts a good converter on the website: http://www.mela.us/committees/hegira.html
Catalogers can also use the following book to convert dates:
Wüstenfeld-Mahler'sche Vergleichungs-Tabellen zur muslimischen und iranischen Zeitrechnung : mit Tafeln zur Umrechnung orient-christlichen Ären. Wiesbaden : Deutsche Morgenländische Gesellschaft, 1961.