Kumar, Akhil
Penn State University, USA - XML-based workflow modeling languages (XRL). Includes a list of his publications, some of which are available as PDFs.
http://www.personal.psu.edu/faculty/a/x/axk41

ter Hofstede, Arthur
Queensland University of Technology, Brisbane, Australia - Workflow and electronic services. Contains an overview of his research projects and links to his papers in PDF format.
http://sky.fit.qut.edu.au/~terhofst/

zur Muehlen, Michael
Stevens Institute of Technology, Hoboken, USA - Business activity monitoring, process integration, and standardization. Contains publications in PDF format, links, a discussion forum, his resume, and some research commentary.
http://www.workflow-research.de

Shen, Minxin
National Chiao Tung University, Taiwan - View-based workflow modeling. Includes a list of publications, some available in PDF.
http://www.iim.nctu.edu.tw/~shen

Ellis, Clarence (Skip)
University of Colorado, Boulder, USA - Workflow pioneer. Focus on general groupware and workflow concepts. Contains link to his papers and vita.
http://www.cs.colorado.edu/~skip/Home.html

Dustdar, Schahram
Technical University of Vienna, Austria. Research on Process-oriented Information systems, Service-oriented Computing, and Distributed and Mobile Collaboration. PDF versions of research papers are available.
http://www.infosys.tuwien.ac.at/Staff/sd/

Fakas, George
Manchester Metropolitan University, UK. Research on Peer to Peer and Grid Workflow Architectures. List of publications, but no PDFs.
http://www.docm.mmu.ac.uk/STAFF/G.Fakas/

Bussler, Christoph
Research Foundation Ireland Professor at DERI. Contains his vita and a list of his publications.
http://hometown.aol.com/chbussler/

Dumas, Marlon
Researcher at Queensland University of Technology, Brisbane, Australia, in the area of Web Services composition and flexible application architectures.
http://sky.fit.qut.edu.au/~dumas/

Sheth, Amit
Researcher at the University of Georgia, Athens, GA, USA. Contains his vita and a list of talks and papers, some in PS and PPT format.
http://lsdis.cs.uga.edu/~amit/

Grefen, Paul
Researcher at TU Eindhoven, the Netherlands, in the area of cross-organizational workflow management. Contains his publications, some are available as PDF.
http://is.tm.tue.nl/staff/pgrefen/

Neubauer, Thomas
Vienna University of Technology, Austria, Research on Workflow Management, Security and Valuation.
http://www.ifs.tuwien.ac.at/~neubauer/

van der Aalst, Wil
TU Eindhoven, the Netherlands - Workflow mining and Petri-net-based modeling languages. Includes a list of publications, some papers in PDF format, and links to his projects.
http://is.tm.tue.nl/staff/wvdaalst/

Ludwig, Heiko
Researcher at IBM Watson Labs, Yorktown, NY, USA, in the area of workflow and web services. Contains information about his projects and a list of his papers, most of which are available as PDF files.
http://domino.research.ibm.com/comm/research_people.nsf/pages/hludwig.index.html

Zhao, J. Leon
University of Arizona, USA, - Inter-organizational workflow management. Includes a list of his publications, some of which are available as PDF files.
http://www.u.arizona.edu/~jlzhao/

Mendling, Jan
Researcher at University of Vienna in the area of process modeling using EPCs and BPEL. Site contains his bio and papers in PDF format.
http://wi.wu-wien.ac.at/home/mendling/