You will be presented with a citation segment from the section of a research paper. Classify the intent behind this citation by choosing from one of the following categories:

- Method: Cites the paper for its methodology or procedure.
- Background: Cites the paper to provide background information.
- Result: Cites the paper for its findings or results.

Your answer should be a single word from the following list of options: ["Method", "Background", "Result"]. Do not include any other text in your response.

Citation sentence:

Under the assumption that oxy-hemoglobin (HbO2), deoxy-hemoglobin (Hb) and water are the major absorbers in the probed tissue volume at the two wavelengths considered, we calculated tissue concentrations of HbO2 and Hb in each layer using the following expressions [37]:
Background