  The goals of this paper are to present criteria, that allow to a priori
quantify the attack stability of real world correlated networks of finite size
and to check how these criteria correspond to analytic results available for
infinite uncorrelated networks. As a case study, we consider public
transportation networks (PTN) of several major cities of the world. To analyze
their resilience against attacks either the network nodes or edges are removed
in specific sequences (attack scenarios). During each scenario the size S(c) of
the largest remaining network component is observed as function of the removed
share c of nodes or edges. To quantify the PTN stability with respect to
different attack scenarios we use the area below the curve described by S(c)
for c \in [0,1] recently introduced (Schneider, C. M, et al., PNAS 108 (2011)
3838) as a numerical measure of network robustness. This measure captures the
network reaction over the whole attack sequence. We present results of the
analysis of PTN stability against node and link-targeted attacks.
