Are languages other than English allowed in Federal Prisons?

Can mail be written in Spanish, for instance?

I ask that because, after searching through the "Mail Management Manual" (5800.16 from April 5, 2011 at https://www.bop.gov/policy/progstat/5800_016.pdf ), I haven't seen anywhere in the document something stating other languages are allowed, nor that they are forbidden.

As opposed to Nevada's rules... "AR 750 Inmate General Correspondence and Mail" at http://doc.nv.gov/About/Administrative_Regulations/Administrative_Regula... clearly says this: "N. Inmates may correspond in their primary language.". This makes things very clear in Nevada.

And also Florida's rules: "33-210.101 Routine Mail" at https://www.flrules.org/gateway/RuleNo.asp?ID=33-210.101 states clearly: "Correspondence shall be written in either English or Spanish. Inmates who cannot read and write in English or Spanish shall request approval from the warden to correspond and receive correspondence in the language which the inmate can read and write using Form DC6-236, Inmate Request."