You seem to be attempting to access an item that has been removed from the repository.
There is an alternative version of the item you are trying to access:
Horne, Ross and Sassone, Vladimiro, (2011) A Verified Algebra for Linked Data Revara, Antonio and Mousavi, MohammadReza (eds.) At 10th International Workshop on the Foundations of Coordination Languages and Software Architectures, EPTCS 58, Germany. , pp. 20-33.