hxcite-mkbib: command not found

Have You tried accessing the binary with the full path?

Maybe Your $PATH variable doesn't contain the default paths? echo $PATH should give something like:

[root@server ~]# echo $PATH
/usr/local/sbin:/usr/local/bin:/sbin:/bin:/usr/sbin:/usr/bin:/root/bin

If it's empty, You may set the PATH variable with this command

export PATH="/usr/local/sbin:/usr/local/bin:/sbin:/bin:/usr/sbin:/usr/bin:/root/bin"

On Debian possible default full paths are:

/usr/bin/hxcite-mkbib - from package: html-xml-utils

You may install the required package with command apt-get install {package}
Error in other languages:
hxcite-mkbib: bevel nie gevind nie
hxcite-mkbib: comandă negăsită
hxcite-mkbib: comando não encontrado
hxcite-mkbib: commande introuvable
hxcite-mkbib: command not found
hxcite-mkbib: käsku ei ole
hxcite-mkbib: không tìm thấy lệnh
hxcite-mkbib: komanda nerasta
hxcite-mkbib: Kommando nicht gefunden.
hxcite-mkbib: kommandot finns inte
hxcite-mkbib: komut yok
hxcite-mkbib: nie znaleziono polecenia
hxcite-mkbib: níor aimsíodh an t-ordú
hxcite-mkbib: no se encontró la orden
hxcite-mkbib: no s'ha trobat l'ordre
hxcite-mkbib: opdracht niet gevonden
hxcite-mkbib: parancs nem található
hxcite-mkbib: perintah tidak ditemukan
hxcite-mkbib: príkaz nenájdený
hxcite-mkbib: příkaz nenalezen
hxcite-mkbib: команда не найдена
hxcite-mkbib: командата не е открита
hxcite-mkbib: 命令找不到
hxcite-mkbib: コマンドが見つかりません