Выражение встречается в следующем контексте:
Подтверждение оригинальности

Я, (такая-то), настоящим подтверждаю, что данная работа выполнена мной лично (и т.д.)

Заранее спасибо

I hereby confirm that this assignment is my own work. In addition, the assignment has not previously been submitted for assessment, either in whole or in part, by either myself or any other student at either Manukau Institute of Technology or at any other tertiary institution. To the best of my knowledge and belief, the assignment contains no material which has been previously published or written by another person except where due reference has been made. All unpublished sources of information have been acknowledged.

HTH