from typing import List
import re


def find_assets(html: str) -> List[str]:
    """
    Return a list of assets found in the given HTML string
    """
    return re.findall(
        r'"([^"]+\.(?:css|js|jpg|jpeg|gif|tiff|png|bmp|svg|ico|pdf))"',
        html, flags=re.IGNORECASE)