In the sentence extracted from biomedical literature, identify all the chemical entities. The required answer format is the same sentence with HTML <span> tags to mark up specific entities. 
### Entity Markup Guides:
Use <span class="chemical"> to denote a chemical.

### Input Text: OBJECTIVE : We aimed to evaluate the rates of cisplatin - induced nephrotoxicity in cancer patients receiving single - agent cisplatin with and without mannitol .
### Output Text:
OBJECTIVE : We aimed to evaluate the rates of <span class="chemical">cisplatin</span> - induced nephrotoxicity in cancer patients receiving single - agent <span class="chemical">cisplatin</span> with and without <span class="chemical">mannitol</span> . 