erc: who: Zardecki, A. what: Reduction of photosynthetically active radiation under extreme stratospheric-aerosol loads when: 19810101 where: https://digital.library.unt.edu/ark:/67531/metadc1086267/ erc-support: who: University of North Texas Libraries what: Permanent: Stable Content: when: 20081203 where: https://digital.library.unt.edu/ark:/67531/