@article{kuehne94,
author = {Thomas K\"uhne},
journal = {ACM SIGPLAN Notices},
month = jul,
note = {Functional programs in pure OO-Languages},
number = {7},
pages = {15--20},
title = {Higher Order Objects in pure Object-Oriented Languages.},
volume = {29},
year = {1994}
}

Also (due to a long story including an editor's moving into a new house and without the responsibility of the author) appeared as

@article{kuehne95c,
author = {Thomas K\"uhne},
journal = {OOPS Messenger},
month = jan,
note = {Functional programs in pure OO-Languages (reprint)},
number = {1},
pages = {1--6},
title = {Higher Order Objects in pure Object-Oriented Languages.},
volume = {6},
year = {1995}
}