In-line and Displayed Mathematics

The equation

utt - Δu + u5 + u$\displaystyle \left\vert\vphantom{ u}\right.$u$\displaystyle \left.\vphantom{ u}\right\vert^{{p-2}}_{}$ = 0 in R3×$\displaystyle \left[\vphantom{ 0,\infty }\right.$0,∞$\displaystyle \left.\vphantom{ 0,\infty }\right[$. ()
is numbered and it also has the label ``wave''. You can use this label to jump to this equation using hypertext links.