List of linked webpages:
[L1] https://reprap.org/wiki/Kossel
[L2] https://www.thingiverse.com/
[L3] https://github.com/MarlinFirmware/Marlin
[L4] http://www.anycubic3d.com/support/show/594034.html
[L5] https://www.arduino.cc/en/Main/Software
[L6] http://reprapltd.com/reprappro/documentation/building-the-paste-extruder/index.html