wordbib2xml: 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 CentOS possible default full paths are:

/usr/bin/wordbib2xml - from package: bibutils

You may install the required package with command yum install {package}

On Debian possible default full paths are:

/usr/bin/wordbib2xml - from package: bibutils

You may install the required package with command apt-get install {package}
Error in other languages:
wordbib2xml: bevel nie gevind nie
wordbib2xml: comandă negăsită
wordbib2xml: comando não encontrado
wordbib2xml: commande introuvable
wordbib2xml: command not found
wordbib2xml: käsku ei ole
wordbib2xml: không tìm thấy lệnh
wordbib2xml: komanda nerasta
wordbib2xml: Kommando nicht gefunden.
wordbib2xml: kommandot finns inte
wordbib2xml: komut yok
wordbib2xml: nie znaleziono polecenia
wordbib2xml: níor aimsíodh an t-ordú
wordbib2xml: no se encontró la orden
wordbib2xml: no s'ha trobat l'ordre
wordbib2xml: opdracht niet gevonden
wordbib2xml: parancs nem található
wordbib2xml: perintah tidak ditemukan
wordbib2xml: príkaz nenájdený
wordbib2xml: příkaz nenalezen
wordbib2xml: команда не найдена
wordbib2xml: командата не е открита
wordbib2xml: 命令找不到
wordbib2xml: コマンドが見つかりません