\beamer@slide {fig:h1}{4} \beamer@slide {fig:h2}{4} \beamer@slide {fig:homo}{4} \beamer@slide {eq:pd}{12} \beamer@slide {eq:ps}{12} \beamer@slide {fig:r2}{15} \beamer@slide {fig:r1}{15} \beamer@slide {fig:rel}{15} \beamer@slide {fig:heter}{22} \beamer@slide {eq:perf}{22}