The rule that once the terms of any contract have been proved by documentary evidence, no evidence of any oral statement shall be admitted for contradicting such terms has ________ provisions establishing variations to the rule.

Under Section 91-100 of the Evidence Act, there are 6 main provisions that establish exceptions/variations to the parol evidence rule (that documentary evidence excludes oral evidence of contract terms). These include: cases of ambiguity (Section 94), distinct oral agreements (Section 95), representation by fraud/mistake (Section 96), promise/representation in writing (Section 97), rescission/modification/voidability (Section 98), and persons needing rescission (Section 99). These sections allow oral evidence to contradict, vary, or add to written contract terms in specific circumstances.