order of second instance
non-uniform second order difference operator
nonlinear second order system
nonlinear second order optical susceptibility
nonlinear second order optical susceptibilities
nonlinear second order optical property
multivarate second order abstract equation
modified first order second moment method
matrix second order system
linear second order moment
linear Hamilton equation of second order
linear equations of second order
linear equation of the second order
linear elliptic system of second order