I know SPF stands for Cadence Standard Parasitic Format (DSPF/RSPF are two types of SPF); also i have use SPEF/SBEF files and i know the general difference among them, but i want to have a deeper understanding of the SPF format or syntax while i coundn't find materials (though there're some on Wiki or VLSI concepts websites, still not specific enough).
Could anyone please advise in which EDA tool's documentation I can find the introduction to the syntax of SPF files? Or is there such a document available? If not, where can I find systematic learning materials on this topic?