The contribution of pomeron fusion to the cross section of η and η′
productions in double-diffractive scattering has been calculated within the
Donnachie-Landshoff model of pomeron. It is shown that the double pomeron
exchange mechanism does not explain the full set of the recent data of WA102
Collaboration, though it might not be inconsistent with η′ productions.Comment: 6 pages, Latex, 3 figure