Baltagi, B.H. and Griffin, J.M. (1983). Gasoline Demand in the OECD: An Application
of Pooling and Testing Procedures. European Economic Review, 22, 117--137.
if(!requireNamespace("lattice")) q()
data("OECDGas")
library("lattice")
xyplot(exp(cars) ~ year | country, data = OECDGas, type = "l")
xyplot(exp(gas) ~ year | country, data = OECDGas, type = "l")