diff --git a/zk/The_Pragmatic_Programmer_1999.md b/zk/The_Pragmatic_Programmer_1999.md
index c705c77..4bbfa7f 100644
--- a/zk/The_Pragmatic_Programmer_1999.md
+++ b/zk/The_Pragmatic_Programmer_1999.md
@@ -2,6 +2,8 @@
 tags: []
 ---
 
+# The Pragmatic Programmer (Hunt/Thomas, 1999)
+
 ## General
 
 ### Meyer's Uniform Access Principle
diff --git a/zk/Theorems_and_empty_sets.md b/zk/Theorems_and_empty_sets.md
index f551549..b9a7d60 100644
--- a/zk/Theorems_and_empty_sets.md
+++ b/zk/Theorems_and_empty_sets.md
@@ -4,12 +4,13 @@ tags:
   - logic
 ---
 
+# Theorems and empty sets
+
 We know that when we construct a
-[derivation](Formal_proofs_in_propositional_logic.md#derivation-rules)
-we start from a set of assumptions and then attempt to reach a proposition that
-is a consequence of the starting assumptions. However it does not always have to
-be the case that the starting set contains members. The set can in fact be
-empty.
+[derivation](Formal_proofs_in_propositional_logic.md#derivation-rules) we start
+from a set of assumptions and then attempt to reach a proposition that is a
+consequence of the starting assumptions. However it does not always have to be
+the case that the starting set contains members. The set can in fact be empty.
 
 _Demonstration_
 
diff --git a/zk/Truth_trees.md b/zk/Truth_trees.md
index b942e39..94d8cb0 100644
--- a/zk/Truth_trees.md
+++ b/zk/Truth_trees.md
@@ -4,6 +4,8 @@ tags:
   - propositional-logic
 ---
 
+# Truth trees
+
 ## Rationale
 
 Like [truth-tables](Truth-tables.md), truth-trees are a means of graphically
diff --git a/zk/Turing_machines.md b/zk/Turing_machines.md
index 79c5452..aaa3f65 100644
--- a/zk/Turing_machines.md
+++ b/zk/Turing_machines.md
@@ -4,6 +4,8 @@ tags:
   - Turing
 ---
 
+# Turing Machines
+
 ## What is a Turing Machine?
 
 Turing Machine is a machine that contains mutable state, executes sequences of
diff --git a/zk/Utilities_operators_flags.md b/zk/Utilities_operators_flags.md
index 325a23a..4d6dedb 100644
--- a/zk/Utilities_operators_flags.md
+++ b/zk/Utilities_operators_flags.md
@@ -3,6 +3,8 @@ tags:
   - shell
 ---
 
+# Utilities, operators, flags in Bash
+
 The following are useful built-in utility methods that you can use for checking
 and validation in the course of your bash scripts.
 
diff --git a/zk/Validity_and_entailment.md b/zk/Validity_and_entailment.md
index e806f1b..1cf08de 100644
--- a/zk/Validity_and_entailment.md
+++ b/zk/Validity_and_entailment.md
@@ -4,7 +4,7 @@ tags:
   - logic
 ---
 
-## Validity
+# Validity and entailment
 
 ### Informal definition
 
diff --git a/zk/Variables_and_data_types_in_Bash.md b/zk/Variables_and_data_types_in_Bash.md
index 024a0cf..d827b6e 100644
--- a/zk/Variables_and_data_types_in_Bash.md
+++ b/zk/Variables_and_data_types_in_Bash.md
@@ -3,6 +3,8 @@ tags:
   - shell
 ---
 
+# Variables and datatypes in Bash
+
 ## Types
 
 ## Variables
diff --git a/zk/Working_with_CSVs_in_Python.md b/zk/Working_with_CSVs_in_Python.md
index e115a29..f2288b3 100644
--- a/zk/Working_with_CSVs_in_Python.md
+++ b/zk/Working_with_CSVs_in_Python.md
@@ -4,7 +4,7 @@ tags: [python, csv]
 created: Sunday, April 28, 2024
 ---
 
-# Working_with_CSVs_in_Python
+# Working with CSVs in Python
 
 ## Core package
 
diff --git a/zk/Zero_property_of_multiplication.md b/zk/Zero_property_of_multiplication.md
index 52b55ca..bba2bd3 100644
--- a/zk/Zero_property_of_multiplication.md
+++ b/zk/Zero_property_of_multiplication.md
@@ -4,6 +4,8 @@ tags:
   - theorems
 ---
 
+# Zero property of multiplication
+
 **Let $a$ represent any member of $\mathbb{W}$ or $\mathbb{Z}$ then:**
 
 $$ a \cdot 0 = 0 $$