The spelling of the surname "Mathisen" can be explained using the International Phonetic Alphabet (IPA). The name is pronounced as /məˈθaɪsən/ in IPA. This is broken down into individual sounds: "m" as in "man," "ə" as in "about," "θ" as in "thin," "aɪ" as in "eye," "s" as in "see," and "ən" as in "button." Hence, the spelling of "Mathisen" accurately captures the phonetic sounds of the name.