@book{hydrographical+surveying+a+description+of+the+means+and+methods+employed+in+constructing+marine+charts,
    author = {Wharton, William J. L.},
    title = {Hydrographical surveying : a description of the means and methods employed in constructing marine charts},
    address = {London},
    publisher = {John Murray},
    date = {1898}
}