This is a sequel to my previous question. @Carlo's response here (to my comment) prompted me to ask this question:

As mentioned in the textbook "Introduction to Percolation Theory" (Chapter 4) by Stauffer *et al.*, the variation of spanning cluster percolation probability $\Pi$ in a finite $L < \infty$ square lattice has the following nature:

Does anyone know any reference where similarly the variation of $\Pi$ is shown for **different** finite values of $L$?

Ideally something like Figure 3 of the paper linked by @Carlo but with $p$ instead of "seed mass" on the $x$-axis.

I ask because upon reading the linked paper, I'm not very convinced that $p$ is proportional to "seed mass". However, if someone could explain why exactly seed mass should be considered to be analogous to $p$, that would be an acceptable answer too.