| http://www.greenlivingcentre.org.uk/ctc |
| http://www.tandem-club.org.uk/ |
| http://www.bikeforall.net/ |
| http://www.sheldonbrown.com/home.html |
| http://www.bbinstitute.com/manual.htm |
| http://www.sustrans.org.uk/ |
| http://www.thetandemlink.com |
| http://cycle.shimano-eu.com/publish/content/cycle
|
| http://www.fillthathole.org.uk/ |
| http://www.cycle-route.com/ |