Cyber-Physical Systems (CPS) are heterogeneous and require cross-domain expertise to model. The complexity of these systems leads to questions about prevalent modeling approaches, their ability to integrate heterogeneous models, and their relevance to the application domains and stakeholders. The methodology for Multi-Paradigm Modeling (MPM) of CPS is not yet fully established and standardized, and researchers apply existing methods for modeling of complex systems and introducing their own. No systematic review has been previously performed to create an overview of the field on the methods used for MPM of CPS. In this paper, we present a systematic mapping study that determines the models, formalisms, and development processes used over the last decade. Additionally, to determine the knowledge necessary for developing CPS, our review studied the background of actors involved in modeling and authors of surveyed studies. The results of the survey show a tendency to reuse multiple existing formalisms and their associated paradigms, in addition to a tendency towards applying transformations between models. These findings suggest that MPM is becoming a more popular approach to model CPS, and highlight the importance of future integration of models, standardization of development process and education.