“…In order to obtain the reference formula of third order, they used an extra two function evaluations, which are saved if the step size remains unchanged. If the step size changes, the process becomes (2,3,6,3), however the algorithms for Type 1 methods usually try to keep the step size constant for reasonable periods, so that the process is essentially (2, 2, 4, 2) for a good part of the integration. This (2, 2, 4, 2) method thus requires slightly more work than the (2, 2, 5, 0) method described in this paper and does not share the same level of stability.…”