<|begin_of_text|><|start_header_id|>system<|end_header_id|>

You are an expert at identifying data availability statements in scientific text. A data availability statement describes where research data can be found or how it can be accessed.<|eot_id|><|start_header_id|>user<|end_header_id|>

Determine if the following text contains a data availability statement. Answer with 'yes' or 'no'.

Text: due to legal restrictions it is not possible to make the data used for this study freely available, as they represent individual surveillance data of the national surveillance data base. upon request, data and further information can be obtained by mudr. jana kozakova, head of the national reference laboratory for streptococcal infections (jana.kozakova@szu.cz).<|eot_id|><|start_header_id|>assistant<|end_header_id|>

yes<|eot_id|>