DOC: Add back reference to blackbody doc
DOC: Add back reference to blackbody doc

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larrybradley/astropy,lpsinger/astropy,mhvk/astropy,aleksandr-bakanov/astropy,astropy/astropy,aleksandr-bakanov/astropy,larrybradley/astropy,aleksandr-bakanov/astropy,pllim/astropy,saimn/astropy,larrybradley/astropy,aleksandr-bakanov/astropy,astropy/astropy,pllim/astropy,larrybradley/astropy,pllim/astropy,lpsinger/astropy,saimn/astropy,mhvk/astropy,dhomeier/astropy,pllim/astropy,dhomeier/astropy,mhvk/astropy,StuartLittlefair/astropy,StuartLittlefair/astropy,astropy/astropy,astropy/astropy,mhvk/astropy,dhomeier/astropy,StuartLittlefair/astropy,saimn/astropy,dhomeier/astropy,lpsinger/astropy,StuartLittlefair/astropy,StuartLittlefair/astropy,lpsinger/astropy,saimn/astropy,lpsinger/astropy,dhomeier/astropy,larrybradley/astropy,pllim/astropy,saimn/astropy,astropy/astropy,mhvk/astropy