Ocean Waves: Stationary Random Theory

[Milo Schield]

In the 1983 Guinness Book of World Records under OCEANS, the following
appears concerning the heights of waves:
"It has been calculated on the statistics of the Stationary Random theory
that one wave in more than 300,000 may exceed the average by a factor of 4."

What is a reference on Stationary Random statistical theory?
What assumptions are involved in modeling random interactions of waves?
What is the sampling distribution for the heights of "random" waves?