摘要：Equation (9), representing the phase φ(t) at time t of a periodic
variableundergoinga periodchange,is erroneous.This equation
should instead read
φ(t) = N E (t) − ?N E (t)?, (1)
where N E (t) is the number of cycles elapsed at time t since a re-
ference epoch E. The quantity N E (t) for a constant rate of period
change is given by
N E (t) =
1
β
ln
?
1 +
β
P 0
(t − E)
?
, (2)
?
Based on observations collected at the Indian Astrophysical
Observatory, Hanle, India.
where β is the period change rate and P 0 is the period at the
epoch E.
