Brackets in brackets, braces in braces

[Horvath, Arpad]

How can I find strings like this with regular expressions:\something
[something1] {something2} {something3}Where in the braces can be also
another braces. For example:\frac{1\times10^{-16}}{4}   can be at the
place, where something2 is.(braces in pairs)\interval [J]
{\frac{1\times10^{-16}}{4}} {1..5}My half solution is at
www.szgti.bmf.hu/~ahorvath/regexp.txt.