lim+, delta+, and Non-Permutability of beta-Steps.

@article{pub8618,
    author = {

Wirth, Claus-Peter
},
    title = {lim+, delta+, and Non-Permutability of beta-Steps.},
    year = {2012},
    volume = {47},
    pages = {1109--1135},
    journal = {Journal of Symbolic Computation},
    publisher = {Academic Press, Elsevier}
}