Links
[1] https://www.hootsgo.org/?q=node/6404
[2] https://www.physics.ohio-state.edu/p670/textbook/Chap_4.pdf
[3] http://en.wikipedia.org/wiki/Heat_transfer
[4] http://zebu.uoregon.edu/~soper/Physics/thermaltransfer.html
[5] http://www.energyeducation.tx.gov/energy/section_1/topics/forms_of_energy/thermal_energy.html