BOOK I-GENERAL PART
TITLE II-THE ACT
CHAPTER II-FORMS OF CRIME
Article 26
Authorship
He who performs the act, by himself or by someone as an intermediary, or who directly participates in its execution, in agreement or together with other person, or other persons, or who intentionally determines other person to carry out the act, is punishable as principal, if there has been execution or the beginning of execution.
Commission through another person
Individual commission
Joint commission
EDIT.