I can't find anywhere on the Internet what these things actually refer to, just plenty of things referencing them. I have a vague description of P, Q and R branches but I don't really understand it from that. And as for O lines and S lines??? I can't find an explanation anywhere. I need to know how they arise and how you identify them, I guess.
Also are lines and branches different? I suppose they are...
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Also are lines and branches different? I suppose they are...
x