I found this lecture by Abul-Hasan Malik (hafidhahullah Ta'ala) on a random 4Shared account. It was posted there over 15 years ago.
It is a nice and simple introduction the six well-known collections of Hadeeth.
I have carried out a search over the internet and have not been able to find another source for this particular audio.
After having edited it, I now present it here for us all to benefit from, walhamdulillah.
Abu Hurairah (رضي الله عنه) narrated that the Prophet ﷺ said: "Whoever invites to guidance will be rewarded like those who follow him in the guidance are rewarded, and that will not decrease the reward of those who have followed him." [Collected by Imām Muslim]
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