$ apt list | grep mono | grep i18n

WARNING: apt does not have a stable CLI interface. Use with caution in scripts.

libmono-i18n-cjk4.0-cil/xenial,xenial 4.2.1.102+dfsg2-7ubuntu4 all
libmono-i18n-mideast4.0-cil/xenial,xenial 4.2.1.102+dfsg2-7ubuntu4 all
libmono-i18n-other4.0-cil/xenial,xenial 4.2.1.102+dfsg2-7ubuntu4 all
libmono-i18n-rare4.0-cil/xenial,xenial 4.2.1.102+dfsg2-7ubuntu4 all
libmono-i18n-west4.0-cil/xenial,xenial 4.2.1.102+dfsg2-7ubuntu4 all
libmono-i18n4.0-all/xenial,xenial 4.2.1.102+dfsg2-7ubuntu4 all
libmono-i18n4.0-cil/xenial,xenial 4.2.1.102+dfsg2-7ubuntu4 all