Please expand.
Plotkin, Gordon D. 1977. ‘LCF Considered as a Programming Language’. Theoretical Computer Science 5 (3): 223–55. https://doi.org/10.1016/0304-3975(77)90044-5.
@article{plotkin_lcf_1977,
title = {{LCF} considered as a programming language},
volume = {5},
doi = {10.1016/0304-3975(77)90044-5},
number = {3},
journal = {Theoretical Computer Science},
author = {Plotkin, Gordon D.},
year = {1977},
pages = {223--255}
}
Ong, C.-H. L. 1995. ‘Correspondence between Operational and Denotational Semantics: The Full Abstraction Problem for PCF’. In Handbook of Logic in Computer Science, edited by S. Abramsky, Dov M. Gabbay, and T. S. E. Maibaum. Vol. 4. Oxford University Press. [pdf]
@incollection{ong_correspondence_1995,
title = {Correspondence between operational and denotational semantics: the full abstraction problem for {PCF}},
volume = {4},
booktitle = {Handbook of {Logic} in {Computer} {Science}},
publisher = {Oxford University Press},
author = {Ong, C.-H. L.},
editor = {Abramsky, S. and Gabbay, Dov M. and Maibaum, T. S. E.},
year = {1995}
}