nroff, troff, vi for ms-dos

[Michael Robinson]

I am looking for the following to run under MS-DOS:

    1.  A full-featured BSD-style "vi" program.

    2.  An "nroff" that supports Berkeley macro packages.

    3.  A "troff", as above, that will format output for an
        HP-compatible laser printer.

Products could be public domain, shareware, or commercially offered
packages.  If you can help me with relevant information, please send
mail to this account (I'm not a regular reader of this group).
Many thanks.

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Michael Robinson                             USENET:  ucbvax!cogsci!robinson
                                             ARPA: robinson at cogsci.berkeley.edu