I am working on some problems related to primes $q$ of the form $q = 4p+1$ where $p$ is also prime. The infinitude of such primes is still open. But recently I found that If I were to count the number of such primes up to x, I should expect to find $Cx/(\log x)^2$ of them. Can anyone suggest any reference to this result? Or some references where I can find such a result with proof.