matitac: command not found

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/matitac - from package: matita

You may install the required package with command apt-get install {package}

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