Growing network models with preferential attachment dependent on both age and
degree are proposed to simulate certain features of citation network noted in
\cite{red2}. In this directed network, a new node gets attached to an older
node with the probability ∼K(k)f(t) where the degree and age of the older
node are k and t respectively. Several functional forms of K(k) and
f(t) have been considered. The desirable features of the citation network can
be reproduced with K(k)∼k−β and f(t)∼exp(αt) with
β=2.0 and α=−0.2 and with simple modifications in the growth
scheme.Comment: 6 pages, 6 figure