Researchr is a web site for finding, collecting, sharing, and reviewing scientific publications, for researchers by researchers.
Sign up for an account to create a profile with publication list, tag and review your related work, and share bibliographies with your co-authors.
S. El-Kassas. Visual languages their definition and applications in system development. Journal of Systems Architecture, 32(1-5):383-391, 1991. [doi]
Abstract is missing.