tõestamisele
tõestamisele is the dative singular form of the Estonian word tõestus, which translates to "proof" or "evidence" in English. The dative case in Estonian is used to indicate the indirect object of a verb, the recipient of an action, or sometimes the purpose or goal of an action. Therefore, tõestamisele typically appears in sentences where something is being given, shown, or directed towards proof or evidence.
For instance, one might say "Ta andis oma avalduse tõestamisele" which translates to "He gave his statement