Cubic Spline solutions to Fourth-order Boundary Value Problems
The cubic spline approximation to the fourth-order
differential equation y''''+p(x)y''+q(x)y'+r(x)y=t(x) 
is shown to reduce to the solution of a five-term recurrence
relationship.  For some special cases the 
approximation is shown to be simply related to a finite
difference representation with a local truncation 
error of order (y/720)delta^8.
CACM June, 1973
Hoskins, W. D.
