Some key references on CCW:

Hayward, Wes. Analog Circuitry for a CCW Receiver. CCWN, 7S:3.

Woodson, Chas. Frequency Standard Temperature Compensation, CCWN 75:5.

Petit, Ray. Fundamentals of CCW. CCWN 75:7.

Petit, Ray. Assembly and Operation of the Coherent CW Filter, CCWN i5:1,

Woodson, Chas. Ways of Setting the Phase of CCW Keying and
Filtering, CCWN 75:22.

Woodson, Chas. Limits of Communication Due to Propagation Conditions,
CCWN 7S:23.

McCaskey, Andy. The Coherent TEN-TEC: A Practical CCW Station
Assembly, CCWN 75:24.

Woodson, Chas. Conversion of the HD-10 Keyer to CCW, CCWN 75:43.

Petit, Ray and Woodson, Chas. Receiver Design for CCW, CCWN 75:44.

Woodson, Chas. JA-W6 Test of CCW, CCWN 75:51.

Woodson, Chas. CCW Lecture Outline, CCWN 75:52.

Woodson, Chas. A Portable CCW Transmitter, CCWN 75:53.

Petit, R. C. Coherent CW: Amateur Radio's New State of the Art?
QST, 1975, September, 26-27.

Woodson, Chas. Design of a High Quality CW Receiver, CCWN 75:55.

Woodson, Chas. Introduction to CCW, CCWN 75:57-59.

Woodson, Chas. Stabilization of the SB-303 Receiver for CCW, CCWN 75:60.

Petit, Ray. Synthesizer for 5-5.5 MHz, CCWN 76:65-66.

Petit, Ray. More thoughts on Receiver Design for CCW, CCWN 76:67.

Sekine, Kaytaro. What is Coherent CW? (in Japanese) Ham Radio
Journal, January, 1976, 79-85.