The spelling of the word "busse" can be confusing, as it is not commonly used in English. However, the correct spelling is with double "s" at the end. In IPA phonetic transcription, it would be /bʌs/. The "u" sound is a short vowel sound, similar to "uh". The "s" sounds are pronounced as voiceless alveolar fricatives, which means the airflow is restricted at the alveolar ridge. Despite its unusual spelling, "busse" can be easily pronounced once its phonetic transcription is understood.