Electron capture or positron emission?

Regarding to the latest test you guys took on Nuclear Physics, question 9 states that ⁶⁴Cu decays into ⁶⁴Ni isotope by means of positron emission (Schaum’s Outlines’ Applied Physics 4th Edition). But if you pay a visit to webelements at this hyperlink you’ll see that ⁶⁴Cu decays into ⁶⁴Ni by means of electron capture. Which one is correct? I don’t know for sure, butI know that whether by positron emission or electron capture, both type of decay would resulted in proton being converted to neutron.