Persian NACO Manual
Dates for Classical Authors
Examples of many situations and treatments can be found in the NAF.
A few rules seem to define current LC practice, as deduced from
communications to us.
- If the piece in hand or reference source gives only Miladi dates,
transcribe the years as given.
- Unless day and/or month are cited, whether in the piece in
hand or in an outside reference source, a Hijri year is always to
be transcribed in a heading as a choice of two Miladi years
connected by "or" (except when a Hijri year falls entirely
within one Miladi year). This practice is to be followed even if
the piece in hand or reference source provides the Hijri date
with a "corresponding" single Miladi date, as LC
considers such correspondences, unless accompanied by days
and/or months, to be mere "guesses."
- If the piece in hand and a reference source disagree on an
author's dates, consult a third source (i.e., a second reference
source) if available. If no third source can be found, or if the
information from the third source does not "break the tie," cite all
three sources and give the dates in the heading in a compromising
form, using "?," "ca.," "fl.," "Xth cent." and Xth/Yth cent." as
outlined in 22.17. A single "fl." year given by a reference source
does not justify the use of any date in the heading, unless to
resolve a conflict with another heading.