It was narrated that:
Muhammad bin Salamah said: "I proposed marriage to a woman, then I hid and waited to see her until I saw her among some date palm trees that belonged to her." It was said to him: "Do you do such a thing when you are a companion of the Messenger of Allah?" He said: "I heard the Messenger of Allah saying: 'When Allah causes a man to propose to a woman, there is nothing wrong with him looking at her.' "
English reference: Vol. 3, Book 9, Hadith 1864
Arabic reference: Book 9, Hadith 1937