RFC 2331
ATM Signalling Support for IP over ATM - UNI Signalling 4.0 Update. M. Maher. April 1998.
http://tools.ietf.org/html/rfc2331

Theory of Honest Signalling
Costly signalling and Zahavi's handicap principle in animal communication: sexual selection, signalling among relatives, and in human communication.
http://octavia.zoology.washington.edu/handicap/

Cellular Signalling
Papers covering all aspects of mechanisms, actions and structural components of cellular signalling systems.
http://www.elsevier.com/wps/find/journaldescription.cws_home/525462/description

Railway Signalling Design Training for the UK
UK signalling design courses and other related services for the UK rail industry.
http://www.peak-ict.co.uk/

This Is a Recording
Hundreds of telephone sounds and recordings including error recordings, signalling, colored box tones, and devices.
http://www.thisisarecording.com

Mikko Juusola
studies processing in visual neurons of Drosophila as well as effects of molecular components on neural computations and sensory adaptation. Influence of rearing and environment on signalling is studied and signalling during natural stimulation is analyzed and modeled.
http://www.shef.ac.uk/bms/research/juusola

Atkinson Dynamics
Manufacturers of industrial intercom communication systems and auxiliary products such as speakers and signalling devices for plant-wide communication.
http://www.atkinsondynamics.com/

Whelen Engineering
Design and develop warning and signalling devices. Products include lights and high power voice and siren systems . Product catalogs, technical literature and installation guides available for download .
http://www.whelen.com/

Carl T. Bergstrom - Signalling Theory and Animal Communication
Costly signalling and Zahavi's handicap principle in animal communication: sexual selection, signalling among relatives, and in human communication.
http://octavia.zoology.washington.edu/handicap/

London Rail Recruitment
UK Agency with immediate Rail job vacancies in London always available for Signalling Designers, Signalling Principle Designers, Signalling Design Verifier, Signalling Installers, Signalling Team Leader, Installation Managers, Point Fitters, Locking Fitter (Mechanical and Electrical), Signalling Verification Testers, Signalling Functional Tester, Rail Project Engineers, Signalling Maintainers, Signalling Fault Finder and Managers and Testers to fill Maintenance Vacancies.
http://www.londonrailrecruitment.com