1. A method for detecting an original language of a translated document, comprising: retrieving the translated document; identifying a language of the retrieved document; calculating a language model for the language of the retrieved document (LM(RD)); calculating a distinct vector as a difference between LM(RD) and a common language model for the language of the retrieved document (LMT(RD)); obtaining pair vectors for language model pairs associated with the language of the retrieved document; performing at least one of: i) calculating a vector distance between the distinct vector and each pair vector; and ii) calculating a vector distance between the (LM(RD)) and each pair vector; identifying a given pair vector within a threshold vector distance; and identifying the original language corresponding to the given pair vector as the original language of the retrieved document.