[EE] Figuring out the E and B fields from two dipoles

[Ran4]

Image of the problem:

It should be very straightforward: derivate p twice and insert it into the equation. I can do all that, but what is the R̅ vector supposed to be? I've read the literature, but it uses a different formula (that I'm not allowed to have with me to the exam) and it never defines R̅. Traditionally it's always been r̅ = r̅' - r̅, where r̅' is the end position and r is the start position, so I suppose that means r̅ = (0,0,0).

 

[frogjg2003]

This is definitely not an introductory physics problem. As for what the vectors mean, R is the vector from the dipole to the point of interest, and r is not 0.