IPC – (Association Connecting Electronics Industries) – http://www.ipc.org/
SMTA (Surface Mount Technology Association) – https://www.smta.org/
CPCA (China Printed Circuit Association)- http://www.cpca.org.cn/
Shenyi Technology http://www.syst.com.cn/
Kingboard Laminates http://www.kblaminates.com/
ISO Group http://www.isola-group.com/
Rogers Cooperation http://www.rogerscorp.com/
EAGLE https://www.autodesk.com/
PROTEUS https://www.labcenter.com/
Altium Designer http://www.altium.com/
Circuit Board Manufacturer Directory http://thepcblist.com/
Circuits Assembly http://www.circuitsassembly.com/
Electronic Engineering Times http://www.eetimes.com/
PCB information http://www.pcbinfo.net/
SMT net http://www.smtnet.com/
AVR Freaks http://www.avrfreaks.net/
Arduino https://www.arduino.cc/