Clearance and insulation

• Calculating Creepage and Clearance Early Avoids Design Problems Later
• The Evaluation of Spacings in Electronic Product Design
• European standard: EN60065:2002 "Audio, video and similar electronic apparatus. Safety requirements"
• IPC standard: IPC-2221A "Generic Standard on Printed Board Design"

Current carrying capacity

• Articles on Trace Current/Temperature/Power/Resistance
• IPC standard: IPC-2152 "Standard for Determining Current Carrying Capacity in Printed Board Design"

High-Density BGA

• Designing With High-Density BGA Packages for Altera Devices
• High-Density Design With MicroStar BGAs
• 96 and 114 Ball Low-Profile Fine-Pitch BGA Packages
• Xilinx Device Package User Guide Board Routability Guidelines with Xilinx Fine-Pitch BGA Packages section of the Recommended PCB Design Rules chapter.

Dielectric materials datasheets

• Panasonic R1755C FR-4
• Panasonic R1755V High-Tg FR-4
• Panasonic R1566W Halogen-free FR-4
• Taiwan-Leader FR-4
• Isola DE104 FR-4
• Isola HR370 High-Tg FR-4
• Arlon 85N Polyimide
• Arlon 25FR (Low-Er)
• Rogers 4003C and 4350B (Low-Er)
• Taconic RF-35P (Low-Er)
• Thinflex-A (flexible polyimide)

Miscellaneous topics

• Articles by Doug Brooks, UltraCAD Design