Where can one find the different types of thermistor curves?

I'm trying to source an alternate thermistor for one that became unavailable, and the old part lists on its datasheet "RT curve Y". I know that the RT curves of thermistors differ based on the material and doping concentrations etc, but I can't seem to find any reference material about these different curve types. On a datasheet for another brand of thermistor, there's a specification called "Material System" which I think might be related, listing options F, Y, H, G, etc. Can anyone point me to some free literature online about this? I can't find much useful information from Google or Wikipedia. Thanks much.
Hello there! :)
That's because they're temperature sensors, thermistors,RTD's(Resistance. Temperature. Detector.) And possess (PTC's)Positive Temperature Coefficients or (NTC's) Negative Temperature Coefficients . Every thermistor manufacturer should supply you with their own standard of resistance at a given temperature and that is dependent on classification. Resistance value of thermistors is conducted at a temperature of 25°C or 77°F as a baseline any resistance value at a temperature above or below the before mentioned temperature is dependent on the manufacturer.(IMO)They're just too many manufacturers making temperature sensors along with the controllers for the temperature sensors that are proprietary. To point you in the right direction. (neptronics scientific research all about the curves)
Thermistor curves can be found online on websites selling electronic components or sensors. Thermistors are used to measure the temperature of a material and create an empirical curve that shows how this temperature changes over time. This is useful for monitoring devices such as heaters, air conditioning units, and refrigerators.
Where you might find thermistor curves include product specifications pages for electronics products or sensor data sheets for various types of sensors.