Hydra: an open framework for virtual-fusion of recommendation filters. - Savvas Karagiannidis; Stefanos Antaris; Christos Zigkolis; Athena Vakali (RecSys, 2010)

Towards a User-Aware Virtual Museum. - Christos Zigkolis; Vassiliki A. Koutsonikola; Despoina Chatzakou; Savvas Karagiannidis; Maria Giatsoglou; Andreas Kosmatopoulos; Athena Vakali (VS-GAMES, 2011)

Dissimilarity Features in Recommender Systems. - Christos Zigkolis; Savvas Karagiannidis; Athena Vakali (ICDM Workshops, 2013)

Integrating similarity and dissimilarity notions in recommenders. - Christos Zigkolis; Savvas Karagiannidis; Ioannis K. Koumarelas; Athena Vakali (Expert Syst. Appl., 2013)