Editing Register machine (section)

=== Lambek (1961) atomizes Melzak's model into the Minsky (1961) model: INC and DEC-with-test ===
[[Joachim Lambek|Lambek]] (1961)<ref name="Lambek_1961"/> took Melzak's ternary model and atomized it down to the two unary instructions—X+, X− if possible else jump—exactly the same two that Minsky (1961)<ref name="Minsky_1961"/> had come up with.

However, like the Minsky (1961)<ref name="Minsky_1961"/> model, the Lambek model does execute its instructions in a default-sequential manner—both X+ and X− carry the identifier of the next instruction, and X− also carries the jump-to instruction if the zero-test is successful.