First Sketch: Make an LED Blink - Environmental Monitoring with Arduino [Book]
Blink - CoderDojo Twin Cities Arduino
Pushbutton and Flashing LED with mills() tutorial
Blinking the LED, Arduino Lesson 2. LEDs
Arduino - Blinking LED
Solved Q.3) Recall the Blink Example done in class. You can
Blink Arduino Documentation
Arduino's Blink – Mike's Electro Shack
LED Blinking using ESP8266 - NodeMCU
9 LED Patterns with Arduino
L5: Blinking Two LEDs - Physical Computing
Getting Started with Arduino - LED Blinking